The Clinical Study Of The Lean Body Mass Evaluated By Ultrasound

Object To explore the values of ultrasound in clinical application and nutrition assessment by detecting the skeletal muscle content and morphological changes of skeletal muscle.Methods We divided the experiment into three parts.1.The establishment of the method for measuring the content of skeletal muscle by ultrasoundA total of 106 healthy volunteers were collected and randomly divided into model group and verification group.The body skeletal muscle was measured by body composition and the thickness of the skeletal muscle body(including Lateral forearm,Anterior and posterior upper arm,Abdomen,Anterior and posterior thigh,Anterior and posterior lower leg,Subscapula)was measured by ultrasound.The multivariate regression equation was obtained from the model-development group and validated in the cross-validation group using the approach suggested by Bland and Altman.2.The clinical application of the method measured the content of skeletal muscle by ultrasound52 patients were collected in clinical.Using the multiple regression equation of the first part calculate the body skeletal muscle.The correlation analyze between the body skeletal muscle and the camp of the commonly used assessment index including weight,BMI,SGA,albumin,total number of lymphocytes,upper arm circumference,fold thickness,and body composition detection of skeletal muscle to explore the application of the multivariate regression equation in clinical.According to SGA score,patients were divided into normal group(SGA=7)and malnutrition group(SGA>7).The method mentioned above was applied between normal group and malnutrition of patients with skeletal muscle to observe if this equation can be used in malnutrition patients.3.The study of the morphological changes of skeletal muscle using ultrasound20 patients were randomly collected,divided into normal group(SGA=7)and malnutrition group(SGA>7),with 10 cases in each group.Using ultrasonic inspection assesses the skeletal muscle tissue morphology(select vastus internus as the research object)and record the skeletal muscle morphological parameters(muscle fiber length,pinnate Angle,thickness of the skeletal muscle).Rectus was taken during operation.The morphological and morphological parameters of skeletal muscle,skeletal muscle pathology and ultrastructure examination were used to study the skeletal muscle tissue morphology(rectus)of malnutrition patients.Results1.The establishment of the method for measuring the content of skeletal muscle by ultrasoundA correlations were observed between the site-matched SM mass by Human body composition analyzer measurement and the muscle thickness(including Lateral forearm,Anterior and posterior upper arm,Abdomen,Anterior and posterior thigh,Anterior and posterior lower leg,Subscapula)in the model group(r = 0.284?0.668,P<0.05).The correlation between the computational equation of skeletal muscle and skeletal muscle thickness obtained by stepwise regression analysis was r =0.769,SEE=3.53.There was no significant bias between the skeletal muscle content and the skeletal muscle content of the human component detected by the Bland-Altman analysis in the cross-validation group.That is to say that the skeletal muscle content measured by ultrasound can replace the skeletal muscle content by human body composition in clinical practice.2.The clinical application of the method measured the content of skeletal muscle by ultrasoundThe predicted total skeletal muscle mass obtained by multiple regression analysis is applied in clinical.The result shows that the predicted total SM mass to calculate the content of skeletal muscle was negative to the NRS2002 and SGA,and positively correlated with body weight,BMI,upper arm circumference and fold thickness.That is to say,the predicted total skeletal muscle mass could be used as a parameters of nutritional assessment.3.The study of the morphological changes of skeletal muscle using ultrasoundUltrasound examination revealed that the muscles echo of the malnourished patients was enhanced,and the density was dense,and the arrangement of muscle fibers was blurred and the muscle texture was not clear.Malnutrition among the group of patients with femoral muscle,muscle fiber length(8.95± 1.59)cm than normal nutrition group of patients with muscle fiber length(6.91 ±2.01)cm long,shares the muscles in the middle of the muscle pinnate Angle(7.88± 1.89)° less than normal nutrition among the group of patients with femoral muscle pinnate Angle(10.30± 1.91)° The difference between the two groups was statistically significant(P<0.05).In the patients with malnutrition group,the thickness of femoral muscle fiber(1.19 ± 0.15)cm has no statistically significant(P>0.05)with that in the normal group(1.09 ± 0.21)cm.Pathological examination showed malnutrition patients increase in the number of muscle fiber,morphological diversity and the circular muscle fibers.A few spines shape muscle fibers,angle muscle fibers or sometimes central nucleus in part of the muscle fibers could see in some visual field.Number skeletal muscle fibers(1373±57.4)of malnutrition patients was longer than that in normal nutrition patients(1170±75.5),cross-sectional area(12119.16±2047.07)um2 was less than that in patients with normal nutrition(16749.79±378.83)um2,circumference(426.47± 11.45)um was shorter than that in normal nutrition group(496.28±26.73)um;The area of collagen fibers between the muscle fibers of malnutrition patients(144.99±18.63)um2was more than that in the normal group(87.11± 11.56)um2,and the difference was statistically significant(P<0.05).The Experimental results of Electron microscopy showed that the muscle fibers in the malnutrition group were disorder,the size of the sarcomere was uneven,and the Z line and M line were disorganized.Swelling can be seen in sarcoplasmic reticulum and mitochondrial,and the number is fewer than that in normal nutrition group.The size of muscle fibers was different and the necrotic muscle fibers can be seen.The length of sarcomere(1.94±0.12)um in the malnutrition group was longer than that in the normal group(2.00 ±0.04)um,but the difference was not statistically significant(P>0.05).the A line in patients with malnutrition was shorter(1.33±0.05)um than that in normal nutrition group(1.52±0.03)um,I line was longer(0.61±0.05)um than that in patients with normal nutrition(0.49 + 0.05)um,the number of mitochondria in malnutrition group(10.75±0.96)was less than that in normal nutrition group(16.75± 1.26).Both differences were statistically significant(P<0.05).ConclusionUltrasonography which could calculated the body tissue content and observed the morphological characteristics of skeletal muscle can play an important role in nutritional assessment.