Experimental Study Of Rabbit Bone Ultrasonographic Muscle Repair Road Dynamics

PART IESTABLISHMEND OF SKELETAL INJURY MODEL IN RABBITObjectiveby using a homemade gravity hammer from a certain height free fall, blow to theNew Zealand white rabbits’ after calf, exploring the best crackdown to establishment theskeletal muscle contusion model of rabbit,then modelling successful will lay thefoundation for the contrast-enhanced ultrasound evaluating the dynamic changes betweeninjury and repair of rabbit skeletal muscle.Method32New Zealand white rabbits were divided into two groups according to the differentgender, the female group16and the male group16too, these two groups were randomlydivided into four subgroups of2groups,4groups,6groups,8groups according with thenumber of strikes, each subgroup have four white rabbits. While strike White Rabbit withhomemade gravity hammer, observing the changes of the general state、the life habbitand appearance of injury severity in the rabbits.Rabbits were sacrificed immediately afterthe end of the observation, the pathological specimens will be staining by hematoxylin-eosin (HE), Observeding Pathological findings results,then combining pathology todetermine the best model crackdown.Results2times groups of female and male white rabbits’blow at surface of the skin is visiblea little redness after being hit,subsided after15minutes, pressing the site of blow,thereflection of avoiding is not obvious, from surface view no skin and soft tissue markedlyswollen, white rabbits general state is good, living habits showed no change, diet, drinkingwater was unaffected,and no significant reduction in activity levels. Pathologicalexamination showed there was no obvious muscle cells and cell interstitial edema,hemorrhage, and inflammatory cell infiltration was not obvious performance. Four groups,six groups the skin of blow site is bruising obviously, have so far not subside, pressing thesite of blow,the reflection of avoiding is obvious. The general state of the rabbits were bad, diet and drinking water were reduce,the activity reduced significantly, pathologicalexamination showed muscle cells and cells interstitial edema, degeneration, some werevisible muscle fiber breakage, inflammatory cell infiltration obviously, and can be seenscattered in the distribution of red blood cells. Eight groups of female there were fourrabbits showed fracture, male group three rabbits showed fracture,one showed no fracture,all eight group White Rabbit damage at the skin bruising, petechiae obvious, soft tissuewere obvious swelling, to pressing combat parts the avoiding reflection verysignificantly.Rabbit activity was significantly reduced, basically curled up in the corner ofinactivity. Pathological examination showed muscle cells and cell interstitial edema,muscle fiber breakage and there seen a large number of infiltration of inflammatory cells,red blood cells throughout the full vision.ConclusionThere no significant difference between male and female rabbits in rabbit skeletalmuscle injury model, four and six time is more appropriate for the crackdown in rabbitskeletal muscle injury model. Eight time group is likely to cause a fracture, and thereforethat the crackdown is too large, not appropriate to Modeling. PART ⅡEXPERIMENTAL STUDY OF CONTRAST-ENHANCEDULTRASOUND EVALUATING OF SKELETALMUSCLE’S DYNAMIC CHANGES BETWEENDAMAGE AND REPAIR IN RABBITObjectiveThis article aims to study muscle injury site image characteristics after injury by theultrasound contrast.According CEUS quantitative analysis technology then observed therelationship between the pathological changes and microcirculation dynamically change,verify CEUS is reliable to diagnosis muscle damage and evaluate muscleregeneration,provide a reliable basis for dynamic repair changes of muscle damage byCEUS. Evaluation of microcirculation change by ultrasound contrast after muscledamage,further analysis of capillary angiogenesis, and comparison with the pathologicalresults,evaluated muscle injury repair changes, analysis of the correlation between the two.MethodThe first step is to study the sonographic manifestations after ultrasound contrastduring muscle damage and repair process and carry out quantitative analysis ofangiographic parameters.Depending on the different observation time,the34New Zealandwhite rabbits were randomly divided into eight phases according to injury before and afterat different times. Rabbit muscle contusion model established with homemade gravityhammer.During before injury，immediate damage,1day,3days,7days,14days,21days,28days, inject ultrasound contrast agents in five seconds,start CEUS in CEUSmode.Observe the different performance in different period of time after injury.And applytime-intensity curve quantitative analysis techniques, analyzes the selected area regionalperfusion parameters, including the peak signal Intensity (PI), time to peak intensity(Tp),peak intensity (PI), the peak time (TP),area under the curve (AUC), the averagetransit time (MTT).The second step is to study the regeneration and alteration of muscledamage area capillaries by pathological. The rabbits were killed after the first step of theexperiment,then take damage muscle tissue for pathological examination, first by HEstaining to observe the changes of the capillary number. Then detect CD34proteinexpression using immunohistochemical techniques (two-step), marking with the CD34antibody.We will see vascular endothelial cells is dyed brown[1]. Each slice first in low magnification (×40) to select the focus area which have a larger number of vascular, andthe other at high magnification (×100) to select three horizons to count microvesseldensity (MVD) and averaged. Comparison CEUS results with pathological results,application of statistical software for correlation analysis.Results①CEUS: PI,AUC declined from injury immediately to one day,from three days to21days after the injury increased, there is a more than before significantly increase in21days,there is a decreased in28days after the injury. There were statistically significantdifference in the PI、AUC parameters of CEUS between injury before group andimmediately after the injury,1day,3days,7days,21days. TP, MTT significant rise frominjury immediately to one day after injury.And there was a downward trend from threedays to21days after injury. In the21days was significantly lower than the injury before,has increased by28days. TP、MTT have statistically significant difference between injuryimmediately,1day,3day,7day and21days, compared with before the injury.14days and28days after the injury showed no significant difference compared with before injury in PI,TP, AUC and MTT.②Immunohistochemical results: microvessel density was significantlylower during injury immediately,1day,3days,7days after the injury compared with theinjury before, there was significant difference between them, and14days and28days afterinjury the microvascular density have no significant difference compared with the injurybefore.The microvessel density and damage is more than injury before,the difference wasstatistically significant compared with the two.ConclusionCEUS can dynamic evaluate of the number of microvascular after muscle injury,thenestimate the changes of microcirculation blood flow, so we can use CEUS to evaluate thedynamic repair change process after muscle injury.