CAJ | 학술논문

目的解释骨骼肌1H-MRS中的脂峰形态及其影响因素,建立利用骨骼肌1H-MRS评价肌细胞内脂肪的方法 .方法取5名健康志愿者的小腿胫骨前肌和比目鱼肌区域行1H-MRS检查,改变小腿纵轴与主磁场(B0)之间的角度,观察0.80～1.80 ppm(×10-6)处脂峰形态的变化.体外模型研究采用毛细玻璃管束中灌注大豆油和脂肪乳液,分别模拟肌纤维细胞外、细胞内脂肪,比较脂峰随模璎与B0角度变化的特征.结果小腿骨骼肌在0.80～1.80 ppm处可以观察到3～4个峰,各峰相差约0.20～0.30 ppm;当小腿纵轴与B0所成角度增大时,胫骨前肌肌纤维间隙内的脂肪(EMCL)的亚甲基峰逐渐向右侧移位.体外模型很好地模拟了在体骨骼肌1H-MRS脂峰形态,在0.80～1.80 ppm处出现2组甘油三酸酯亚甲基峰和甲基峰,其中心频率相差0.20～0.30 ppm,分别代表肌细胞内、外脂肪.由于骨骼肌组织肌纤维走行的高度有序性及肌细胞内、外脂肪的分子分布状态不同,两者感应的化学位移不同而表现出波峰的分离.这种肌细胞内外脂肪峰的分离在肌束与B0一致时最大,在两者夹角接近魔角(54.7°)时无法分离.结论骨骼肌1H-MRS中肌细胞内、外脂肪发生分离,是一种无创性评价肌细胞内脂肪含量的有效方法 ;胫骨前肌是进行1H-MRS检查的理想部位.
목적 해석골격기1H-MRS중적지봉형태급기영향인소,건립이용골격기1H-MRS평개기세포내지방적방법 .방법 취5명건강지원자적소퇴경골전기화비목어기구역행1H-MRS검사,개변소퇴종축여주자장(B0)지간적각도,관찰0.80～1.80 ppm(×10-6)처지봉형태적변화.체외모형연구채용모세파리관속중관주대두유화지방유액,분별모의기섬유세포외、세포내지방,비교지봉수모영여B0각도변화적특정.결과소퇴골격기재0.80～1.80 ppm처가이관찰도3～4개봉,각봉상차약0.20～0.30 ppm;당소퇴종축여B0소성각도증대시,경골전기기섬유간극내적지방(EMCL)적아갑기봉축점향우측이위.체외모형흔호지모의료재체골격기1H-MRS지봉형태,재0.80～1.80 ppm처출현2조감유삼산지아갑기봉화갑기봉,기중심빈솔상차0.20～0.30 ppm,분별대표기세포내、외지방.유우골격기조직기섬유주행적고도유서성급기세포내、외지방적분자분포상태불동,량자감응적화학위이불동이표현출파봉적분리.저충기세포내외지방봉적분리재기속여B0일치시최대,재량자협각접근마각(54.7°)시무법분리.결론골격기1H-MRS중기세포내、외지방발생분리,시일충무창성평개기세포내지방함량적유효방법 ;경골전기시진행1H-MRS검사적이상부위.
Objective To elucidate the spectrum of lipid peaks in 1H-MRS of skeletal muscle and it's interpretation,to investigate the utility of 1H-MRS in evaluating intramyecellular lipid (IMCL).Methods 1H-MRS was acquired in vivo on tibialis anterior muscle (TA) and soleus muscle (S) on 5 healthy volunteers.The spectrum of the lipid peak between 0.80 and 1.80 ppm was observed with different angle between the long axis of the calf and B0.Ex vivo phantom was an cluster of capillary tubers filled with soybean oil and fat emulsion,simulating the extramyecellular lipid (EMCL) and IMCL,respectively.The spectra of the lipid peaks were compared using different angles between the phantom and Bo field.Results The lipid spectrum split to 3 to 4 peaks between 0.80 and 1.80 ppm on calf muscles,with 0.20 to 0.30 ppm interval between each neighbouring peak.The methylene peak of EMCL shifted to the right when the angle between long axis of the calf and B0 increased.The phantom could simulate the spectrum of 1H-MRS of the muscle,presenting two peaks with 0.20 to 0.30 ppm chemical shift difference between 0.80 and 1.80 ppm.They are methyl triglyceride and methylene,representing IMCL and EMCL,respectively.The peak splitting could be attributed to the high ordered muscle fibers and their chemical shift difference between inta-and extra-cellular distribution.The interval of IMCL and EMCL peaks attenuated when the angle between the muscle fiber and B0 increased from 0 to the magic angle(54.7°).Conclusion On 1H- MRS spectrum,the peak of the EMCL and IMCL splits.This indicated that 1H-MRS is an applicable method to detect IMCL noninvasively.TA is an optimizing muscle for 1H-MRS study.