A Study Of Pathology Image Analysis Of Tissue Remodeling Caused By Hypertension

Hypertension is a kind of common disease of cardiovascular system. In the research field of pathology about hypertension, the structure changing of tissues and cells in target organ always get much attention and is also the base of hypertension. With the development of technology in computer and digital image processing, the computer analysis of pathology image of hypertension become useful in research of pathogenesis and medicine of hypertension. But the usual image analysis soft is limited and inconvenienced in special image analysis. The main target organs damaged by hypertension are heart, brain and kidney. In these three organs the damage lead to vascular remodel, hypertrophy of cardiac muscle cells, collagens hyperplasia and fiberosis of tissues. To evaluate the pathological changing degree of different organs and tissues, it need different image analysis methods, including different image segment algorithm, measurement index, even different imaging method. So the object of this article is that find suitable image analysis methods for main pathological changes of hypertension. The following works were finished: The image segment and measurement methods of vascular remodeling in hypertension; The modification of analysis methods of collagens hyperplasia in cardiac muscle; The measurement and evaluation methods of hypertrophy of cardiac myofibers. The key in image analysis of vascular remodeling is the segment of vascular cavitys and walls. Here traditional image segment methods including color thresholds and region growing methods were tried to segment vascular but the result were not satisfactory due to the complexity of HE stained image of vascular. The active contour model was also adopted to segment vascular. To apply this method in color image, the definition gradient energy and image energy were adjusted. The segment of vascular wall was difficult. In some condition because the vascular tissue connect with the outside chorion, there is no clear boundary. The segment method based on dilation of mathematics was designed to over come it. Although people have bring forward many image segment methods, but segment by hand is needed in many time. After segment of vascular, some index including the area of vascular cavity, the area of vascular wall, the radius of cavity, the radius of wall, and thickness et al, were measured. An important symptom of remodeling of cardiac muscle is collagens hyperplasia. A technique based on picro-siriusred polarization and image analysis was investigated for evolution of collagens remodeling in myocardium of hypertension. The conventional picro-siriusred polarization method is easy to be affected by extinction phenomena, which will decrease the precision of measurement. A correction that adopt the means of 2 image gotten by spacing 45owere brought forward here, corresponding theory explain was also given. The correction will offer more exact data of collagens and collagens types. Another important symptom of remodeling of cardiac muscle is hypertrophy of cardiac muscle cells, is also the size of cardiac myofibrils become larger than normal. There always is a hard work to measure the size ofso many cardiac myofibrils in cardiac muscle images. A method designed by analysis of gray data of cardiac myofibrils image. To decrease effect of image noise, some filters are adopted. The result shown this method can be used to evaluate the degree of hypertrophy of cardiac muscle cells. Atrial natriuretic peptide(ANP) has diuretic, natriuretic, vasodilatory, and aldosterone-inhibitory effects, and can reduce arterial blood pressure. But ANP is a poor drug due to the susceptibility of ANP to enzymatic attack in the gut and the circulation with a resulting short half time. A technique based on release of the human atrial natriuretic peptide (hANP) from plasmid hANP cDNA transfected Chinese hamster ovary (CHO) cells encapsulated in polycaprolactone (PCL)-capsules was investigated for a potential therapeutic approach to hypertension. The morphological changes,histological changes were investigated post-implantation of PCL-capsules in 2K1C hypertensive rats by these image analysis methods developed in this article. This result demonstrated that the usefulness of encapsulated hANP gene transfected cells as a new tool for hANP gene delivery in studying renovascular hypertension and it is also good for improve pathology damage caused by hypertension.