脂肪肝是指肝臟內的脂肪含量超過肝重量的 5％ 以上，或以肝組織切片超過 10％ 以上的肝細胞有脂肪空泡堆積，作為臨床上判斷脂肪肝的依據。最常引起脂肪肝的是因為後天性代謝疾病，常見的糖尿病、肥胖、血脂異常、代謝症候群等疾患者經常併發脂肪肝症狀。
超音波造影其特性為非侵入式、快速顯影、成本低及使用方便的特點，已經非常普遍的使用在臨床上。在這次的研究中，我們開發以定力量測進行三維超聲波造影並量測出人體中具有代表性部位的皮下脂肪組織局部體積，並且克服了皮褶測量的種種限制，推估受試者全身脂肪分部。本研究招募40位年齡介於20到65歲的脂肪肝病人(20位男性，20位女性) 以超音波系統中B-mode的功能進行皮下脂肪組織造影，同時控制超音波探頭與受試者的皮膚表面接觸所需的力量。所取的影像利用Matlab做影像處理，計算出局部皮下脂肪進行三維重建。並與受試者進行雙光子X光吸收儀(GE Lunar iDXA canner)掃描、生物電阻抗分析(Omron，HBF-370)及肝臟瞬時彈性檢測技術(Fibro Scan 502)取得的身體脂肪組成資料進行交互比對，再將數據進行統計分析，實驗結果得知以超音波量測男性腹部脂肪比例與雙光子X光量測身體脂肪有高度相關(r = 0.93)，以超音波量測女性大腿前側脂肪與腹部脂肪對於雙光子X光量測身體脂肪有高度相關(r =0.88)並計算以超音波局部皮下脂肪來推導的身體體脂的預測方程，由結果得知此種定力量測的超音波三維重建技術有效預測脂肪肝患者身體脂肪含量，並輔助醫師對於病人之診斷。

The diagnosis of fatty liver (steatosis) is made when fat in the liver exceeds 5% by weight or liver tissue sections have vacuoles fat accumulation more than 10% of the liver cells. Fatty liver (FL) is commonly associated with alcohol or metabolic syndrome (diabetes, hypertension, obesity, and dyslipidemia), but can also be due to any one of many causes.
Ultrasound (US) B mode image is an alternative method to measure tissue structure and has proven to be an accurate technique to measure subcutaneous fat volume. In this study, We developed the measurement of three-dimensional ultrasound contrast with force-controlled system to measure the volume of representative body regions of subcutaneous adipose tissue. This method can overcome some limitations of the skinfold thickness measurements. The study recruited 40 patient of fatty liver (20 women and 20 men) between the age of 20 and 65 years to measure specific sites of subcutaneous fat volume. However, pressing the transducer onto the skin with too much force will significantly reduce the subcutaneous adipose tissue thickness. In this study, a force controlled system combined with US transducer was used for 3D subcutaneous fat imaging and reconstruction. Finally, the correlations between body fat percentage and subcutaneous fat in steatosis patients have been investigated. The body fat percentage was determined by dual energy X-ray absorptiometry (DEXA, GE Lunar iDXA canner) , bioelectrical impedance analysis (BIA, Omron，HBF-370) and Fibro Scan and compared with each other, we found the abdomen fat volume have accurately predict body fat mass with dual energy X-ray in men (r = 0.93) and the abdomen and thigh fat volume have accurately predict body fat mass with dual energy X-ray in women (r = 0.88). The correlation between body fat percentage and subcutaneous adipose tissue in normal and steatosis patients have been evaluated.

1. Shirai, K., Obesity as the core of the metabolic syndrome and the management of coronary heart disease. Curr Med Res Opin, 2004. 20(3): p. 295-304.
2. Kopelman, P.G., Obesity as a medical problem. Nature, 2000. 404(6778): p. 635-643.
3. Caterson, I.D., et al., Prevention Conference VII: Obesity, a worldwide epidemic related to heart disease and stroke: Group III: worldwide comorbidities of obesity. Circulation, 2004. 110(18): p. e476-83.
4. Bray, G.A., Medical consequences of obesity. J Clin Endocrinol Metab, 2004. 89(6): p. 2583-9.
5. Kushner, R.F., Body weight and mortality. Nutr Rev, 1993. 51(5): p. 127-36.
6. BUild and blood pressure study, 1959. volume 1. Journal of the American Medical Association, 1960. 172(6): p. 633-633.
7. Hanson, P., et al., Evaluation of somatic and autonomic small fibers neuropathy in diabetes. Am J Phys Med Rehabil, 1992. 71(1): p. 44-7.
8. Vinik, A.I., et al., Diabetic neuropathies. Diabetes Care, 1992. 15(12): p. 1926-75.
9. Singhal, A., Endothelial dysfunction: role in obesity-related disorders and the early origins of CVD. Proc Nutr Soc, 2005. 64(1): p. 15-22.
10. Arcaro, G., et al., Body fat distribution predicts the degree of endothelial dysfunction in uncomplicated obesity. Int J Obes Relat Metab Disord, 1999. 23(9): p. 936-42.
11. Tounian, P., et al., Presence of increased stiffness of the common carotid artery and endothelial dysfunction in severely obese children: a prospective study. Lancet, 2001. 358(9291): p. 1400-4.
12. Resnick, L.M., et al., Direct magnetic resonance determination of aortic distensibility in essential hypertension: relation to age, abdominal visceral fat, and in situ intracellular free magnesium. Hypertension, 1997. 30(3 Pt 2): p. 654-9.
13. Ogden, C.L., et al., Prevalence and trends in overweight among US children and adolescents, 1999-2000. Jama, 2002. 288(14): p. 1728-32.
14. Ogden, C.L., et al., Prevalence of overweight and obesity in the United States, 1999-2004. Jama, 2006. 295(13): p. 1549-55.
15. Peltzer, K., et al., Prevalence of overweight/obesity and its associated factors among university students from 22 countries. Int J Environ Res Public Health, 2014. 11(7): p. 7425-41.
16. Wu, D.M., et al., Prevalence and clustering of cardiovascular risk factors among healthy adults in a Chinese population: the MJ Health Screening Center Study in Taiwan. Int J Obes Relat Metab Disord, 2001. 25(8): p. 1189-95.
17. Ogden, C.L. , et al., Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1960–1962 through 2007–2008. National Center for Health Statistics, 2010. 6(1): p. 1-6.
18. Jansen, P.L., Non-alcoholic steatohepatitis. European Journal of Gastroenterology & Hepatology, 2004. 16(11): p. 1079-1085.
19. Serfaty, L. and M. Lemoine, Definition and natural history of metabolic steatosis: clinical aspects of NAFLD, NASH and cirrhosis. Diabetes Metab, 2008. 34(6 Pt 2): p. 634-7.
20. Williams, C.D., et al., Prevalence of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis among a largely middle-aged population utilizing ultrasound and liver biopsy: a prospective study. Gastroenterology, 2011. 140(1): p. 124-31.
21. Lonardo, A., et al., Non-alcoholic fatty liver disease and risk of cardiovascular disease. Metabolism, 2016. 65(8): p. 1136-1150.
22. Newton, J.L., Systemic symptoms in non-alcoholic fatty liver disease. Dig Dis, 2010. 28(1): p. 214-9.
23. Clark, J.M., The epidemiology of nonalcoholic fatty liver disease in adults. J Clin Gastroenterol, 2006. 40 Suppl 1: p. S5-10.
24. Marceau, P., et al., Liver Pathology and the Metabolic Syndrome X in Severe Obesity. The Journal of Clinical Endocrinology & Metabolism, 1999. 84(5): p. 1513-1517.
25. Arun, J., et al., The prevalence of nonalcoholic steatohepatitis is greater in morbidly obese men compared to women. Obes Surg, 2006. 16(10): p. 1351-8.
26. Dixon, J.B. , et al., Weight loss and non-alcoholic fatty liver disease: falls in gamma-glutamyl transferase concentrations are associated with histologic improvement. Obes Surg, 2006. 16(10): p. 1278-86.
27. Palekar, N.A., et al., Clinical model for distinguishing nonalcoholic steatohepatitis from simple steatosis in patients with nonalcoholic fatty liver disease. Liver Int, 2006. 26(2): p. 151-6.
28. Harnois, F., et al., Prevalence and predictive factors of non-alcoholic steatohepatitis (NASH) in morbidly obese patients undergoing bariatric surgery. Obes Surg, 2006. 16(2): p. 183-8.
29. Adams, L.A. , et al., Treatment of non-alcoholic fatty liver disease. Postgrad Med J, 2006. 82(967): p. 315-22.
30. El Saadany, S., et al., Fibroscan versus liver biopsy in the evaluation of response among the Egyptian HCV infected patients to treatment. The Egyptian Journal of Radiology and Nuclear Medicine, 2016. 47(1): p. 1-7.
31. 栗濬傑, 超音波於脂肪分布診斷與治療之應用, 製造科技研究所. 2014, 國立臺北科技大學: 台北市. p. 66.
32. Heymsfield, S.B., et al., Techniques used in the measurement of body composition: an overview with emphasis on bioelectrical impedance analysis. Am J Clin Nutr, 1996. 64(3 Suppl): p. 478s-484s.
33. Houtkooper, L.B., et al., Why bioelectrical impedance analysis should be used for estimating adiposity. Am J Clin Nutr, 1996. 64(3 Suppl): p. 436s-448s.
34. Wagner, D.R. , et al., Techniques of body composition assessment: a review of laboratory and field methods. Res Q Exerc Sport, 1999. 70(2): p. 135-49.
35. Dittmar, M., Comparison of bipolar and tetrapolar impedance techniques for assessing fat mass. Am J Hum Biol, 2004. 16(5): p. 593-7.
36. Heitmann, B.L., Evaluation of body fat estimated from body mass index, skinfolds and impedance. A comparative study. Eur J Clin Nutr, 1990. 44(11): p. 831-7.
37. Evans, E.M., et al., Body-composition changes with diet and exercise in obese women: a comparison of estimates from clinical methods and a 4-component model. Am J Clin Nutr, 1999. 70(1): p. 5-12.
38. Kohrt, W.M., Preliminary evidence that DEXA provides an accurate assessment of body composition. J Appl Physiol (1985), 1998. 84(1): p. 372-7.
39. Dias, P.C., et al., Evaluation of body composition: a comparison between two systems of bioelectrical impedance. Nutrition & Food Science, 2001. 31(6): p. 304-309.
40. Durnin, J.V. , et al., Body fat assessed from total body density and its estimation from skinfold thickness: measurements on 481 men and women aged from 16 to 72 years. Br J Nutr, 1974. 32(1): p. 77-97.
41. 楊淑惠, et al., 成年人體脂肪測量方法的比較及體脂肪與體位相關性的探討. 臺灣營養學會雜誌, 2006. 31(2): p. 32-39.
42. Kushner, R.F., et al., Validation of bioelectrical-impedance analysis as a measurement of change in body composition in obesity. Am J Clin Nutr, 1990. 52(2): p. 219-23.
43. B.S., B.B. Body Fat / Body Composition Tests. 2011; Available from: http://nutritionfirstfitness.com/articles.php?article=Body_Fat_%2F_Body_Composition_Tests.
44. Hillier, S.E., et al., A comparison of body composition measurement techniques. J Hum Nutr Diet, 2014. 27(6): p. 626-31.
45. Ellis, K.J., Human body composition: in vivo methods. Physiol Rev, 2000. 80(2): p. 649-80.
46. van der Ploeg, G.E., et al., Use of anthropometric variables to predict relative body fat determined by a four-compartment body composition model. Eur J Clin Nutr, 2003. 57(8): p. 1009-16.
47. Prior, B.M., et al., In vivo validation of whole body composition estimates from dual-energy X-ray absorptiometry. J Appl Physiol (1985), 1997. 83(2): p. 623-30.
48. Clasey, J.L., et al., Validity of methods of body composition assessment in young and older men and women. J Appl Physiol (1985), 1999. 86(5): p. 1728-38.
49. Bazzocchi, A., et al., DXA: Technical aspects and application. European Journal of Radiology.
50. 盧聖介, 包覆空氣微脂體於高頻超音波影像與聲學非線性性質研究與應用. 清華大學生醫工程與環境科學系學位論文, 2008: p. 1-87.
51. 王鴻偉, 使用三倍頻發射相位法於對比劑諧波影像. 2007.
52. 吳宇翔, 演化式特徵建構技術應用於B模式超音波醫學影像之自動肝器官疾病診斷, in 資訊工程學系. 2011, 國立臺灣海洋大學: 基隆市. p. 102.
53. 張裕崧, 超音波影像之正規化動差於電腦輔助肝臟診斷之應用, in 電機工程學研究所. 2000, 國立臺灣大學: 台北市. p. 0.
54. 陳思嘉, 靶向超音波於血栓溶解之研究. Graduate Institute of Biomedical Electronics and Bioinformatics College of Electrical Engineering & Computer Science National Taiwan University, 2009.
55. Inoue, M., et al. Automated Discrimination of Tissue Boundaries using Ultrasound Images of" Ubiquitous Echo". in 2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 2007. IEEE.
56. Burcher, M.R., et al., A system for simultaneously measuring contact force, ultrasound, and position information for use in force-based correction of freehand scanning. IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 2005. 52(8): p. 1330-1342.
57. Gilbertson, M.W. , et al., Ergonomic control strategies for a handheld force-controlled ultrasound probe. in 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems. 2012. IEEE.
58. Toomey, C., et al., Technical considerations for accurate measurement of subcutaneous adipose tissue thickness using B-mode ultrasound. Ultrasound, 2011. 19(2): p. 91-96.
59. Pineau, J.-C. , et al., Ultrasound techniques applied to body fat measurement in male and female athletes. Journal of athletic training, 2009. 44(2): p. 142-147.
60. Utter, A.C. , et al., Evaluation of ultrasound in assessing body composition of high school wrestlers. Medicine and science in sports and exercise, 2008. 40(5): p. 943.
61. Leahy, S., et al., Ultrasound measurement of subcutaneous adipose tissue thickness accurately predicts total and segmental body fat of young adults. Ultrasound in medicine & biology, 2012. 38(1): p. 28-34.
62. Marfell-Jones, M.J., A. Stewart, and J. de Ridder, International standards for anthropometric assessment. 2012.
63. Tataranni, P.A. , et al., Use of dual-energy X-ray absorptiometry in obese individuals. Am J Clin Nutr, 1995. 62(4): p. 730-4.
64. Leahy, S., et al., A comparison of dual energy X-ray absorptiometry and bioelectrical impedance analysis to measure total and segmental body composition in healthy young adults. European journal of applied physiology, 2012. 112(2): p. 589-595.
65. Bazzocchi, A., et al., DXA: Technical aspects and application. European journal of radiology, 2016.
66. 顏伯晉, 以軟/硬體共設計方式實現即時內容導向影像檢索. 2007.
67. 林俊宏, 應用影像增強處理之邊界偵測演算法. 中華技術學院學報, 2003(26): p. 310-317.
68. 李金鳳 and 張琬婷, 結合關聯探勘與邊緣偵測之區塊為基的彩色影像修復法. 朝陽學報, 2008(13): p. 545-564.