Bone Age Identification Of Medial Clavicular Epiphysis With CT Image Reconstruction

It is practical value for determination the teenagers whether the age is full of thelegal responsibility age of18years old or not by estimating skeletal age of sternal endof clavicle. The traditional methods mainly based on X-ray radiography. However,sternal end of clavicle and adjacent lung, bronchus, sternum, rib, transverse process ofthoracic vertebra are overlapped each other. As a result of overlapping, there will beobtained false negative or positive film reading results when according to X-rayobservation of epiphyseal growth of sternal end of clavicle, which directly affect thescientifical-ness and accuracy of estimating of skeletal age. In recent years, thescholars at home and abroad have started to use thin layer CT scan technology toestimate skeletal age of the sternal end of clavicle. With the2D and3D CTrecombination technology, the accuracy of the film reading distinctly improves bymaking the shape, size and position of epiphysis displayed clearly.In the study, these CT imaging characteristics, which collected from795teenagers（aged from15to25）from East and South China, were studied through bothsternal ends of clavicles’imagings by thin layer coronal CT scan and axial CT scan,multiplanar reconstruction（MPR）and volume reconstruction（VR）technologies. Theparameters of sternal end of clavicle including the longest diameter of epiphysis, thelongest diameter of metaphysis, their length ratio, area of epiphysis, area of metaphysis, and their area ratio were measured and calculated in order to establishnew classification and make descriptive statistics. Based on the staging method ofSchmeling, integrating the CT imaging reconstruction information of sternal end ofclavicle, the new classification of sternal end of clavicle epiphyseal growth weredivided into1to5stages, and stage2and stage3, respectively, contained a, b and csub-classification. Meanwhile, the typing map of medial clavicular epiphysis weresummarized on VRT images. This new classification has merits of large sample size,wide age range and easy operability. By using CT imaging reconstruction techniquesand analyzing the data which closely related to sternal end of clavicle epiphysealgrowth of teenagers, the feasibility of the staging method could be increased.Exploring the correlation between living ages and VR statistics of medicalclavicular epiphysis with the growth rules of teenager’s medial clavicular epiphysis,and building its mathematical model. These mathematical models were built with thestatistic software of SPSS19.0. Analyze the statistical significant differences of agesand sexes in the area ratio and length ratio of epiphyseal and sternal end. Build themathematical model by the method of least squares. In same age group, it was statedthat the length ratio of epiphyseal and sternal end has significant difference ingenders.it obtained the same result in the length ratio of epiphyseal and sternal end.Itfound that the growth rules of epiphysis of medial clavicular were highly correlatedwith the living ages.The highest accuracies of these mathematical models were70.2%(±1.0year) and85.3%(±1.5year). The mathematical model which have a highaccuracy can be put into practice easily.It can be used to confirm and sustain theconclusion of atlas method,and have an important affect on the study about the singleliving skeletal.