生物分形理论在医学影像学中的应用

Biological fractal theory and its applications in medical imaging

从定性到定量是医学影像学发展的必然趋势,生物分形理论为这一趋势提供了新的理论支持。生物分形是研究生物体内部各层次与整体间的关系,以及对生物体的生化组成、形态、生理和病理等影响的理论。虽然分形理论已经发展为一个复杂的体系结构,但在医学领域中应用还处于初期阶段,分维值的多样性使数值统计缺乏基本统一的既有严格数学定义又简便实用的算法,原始医学图像往往不能直接使用定量方法,要通过去繁求简的手段来突出生物分形特征,不同器官结构各自的分维值仍需大量统计资料的界定,才能为定量诊断提供可靠的依据。尽管如此,生物分形理论蕴涵的"局部所含的信息与整体相似"这一重要思想使定量与定性得到相互统一,其应用必将大大推动医学影像学的发展。

From determining character scantly to fixing quantify of the medical images,an inevitable consequence of developmental medical imaging exists.Biological fractal offers new support for this trend in theory.Biological fractal theory researches the relationship between the internal parts and the whole body of organisms,the influence on biochemical composition,morphology,physiology and pathology as well.The diagnosis of the tumor in brain and electrophysiological reflection of the psychology can be analyzed by fractal dimension to implement quantitative validation on morphology.The fractal feature which the fractal dimension exceeding topological dimension consists in various growth of tumor.The recognition of normal tissue and pathological tissue can be quantitatively analyzed by measuring fractal dimension on the textural feature.Fractal analyzing can be used in studying generation of the tumor blood vessel.Fractal researching has great potentiality in studying the function of air diffusion transferring in lung.Multilevel fractal research can be used in studying gene imaging on molecule imaging.Although having developed a complex system,the fractal theory still finds initially application in domain of medicine.The variety values of the fractal dimension make absence of uniform algorithm which have strict definition and convenient program of mathematics.Usually quantitative method cannot be applied in primal medicine images,the pictures must be simplified to stress the feature of biological fractal by weeding out superfluities,the fractal dimension of different organ must be validated by collecting a vast amount of statistic in order to provide reliable quantitative diagnosis,and more application of new content also need hard explore.However,there is an important idea ＂Parts similar to whole＂ implicated in biological fractal theory,which have utterly superiority of dialectical unity as well as quantitative and nature.Further application of biological fractal will greatly promote the development of medical imaging.