基于CT扫描并图像重组青少年锁骨胸骨端骨龄数学模型

Mathematical Models of the Teenager's Skeletal Age Evaluation Based on CT Scan and Imaging Reconstruction of Medial Clavicular Epiphysis

目的：利用我国青少年锁骨胸骨端骨骺发育变化规律，探讨CT容积再现（volume rendering，VR）数据与生物学年龄的相关性，并建立推断骨龄的数学模型。方法通过对我国华东、华南地区684名15～25周岁青少年双侧锁骨胸骨端进行CT薄层扫描并VR三维图像重组，测量并计算双侧锁骨胸骨端骨骺最长径、干骺端最长径及其长度比、骨骺面积、干骺端面积及其面积比等数据，并建立骨龄推断的数学模型。再将50例训练样本代入数学模型，检验模型的准确性。结果左、右两侧骨骺与干骺端长度比、面积比在同一年龄组男女性间差异具有统计学意义（P〈0.05）。建立的数学模型表明锁骨胸骨端骨骼的发育规律与生物学年龄具有高度的相关性，所有模型的准确率都高于70.5%（±1.0岁）和82.5%（±1.5岁）。结论建立的骨龄数学模型的可操作性强、准确性较高。这不仅可与图谱法相互印证和支持，提高骨龄推断的准确性；同时，该方法对未来研究其他单一部位骨龄推断具有重要的意义。

Objective To explore the correlation between CTvolume rendering （VR） statistics and living age and to build the mathematical models for skeletal age evaluation based on the grow th rules of medi-al clavicular epiphysis of teenagers in China. Methods The thin layer CTscan and VR3D imaging re-construction of both sides of sternal ends of clavicles were exam ined for 684 teenagers aged from 15 to 25 in East and South China. The parameters of sternal end of clavicle including the longest diameter of epiphysis, the longest diameter of metaphysis, their length radio, area of epiphysis, area of meta-physic, their area ratio, and other data were measured and calculated in order to establish mathematical models of skeletal age evaluation. Fifty trained subjects were tested to verify the accuracy of the math-ematical models. Results In the same age group, the length ratio and the area ratio had significant dif-ference in genders （P〈0.05）. The established mathematical models showed that the grow th rules of medial clavicular epiphysis were highly correlated with the living ages. The accuracies of these models were higher than 70.5% （±1.0 year） and 82.5% （±1.5 year）. Conclusion The mathematical models have easy operability and high accuracy. It can be used to confirmand sustain the conclusion of atlas method. M eanw hile, it is of great significance to study the other single skeletal age evaluation in the future.