磁共振3D-IDEAL-IQ技术定量评估2型糖尿病大腿肌肉脂肪浸润

目的:采用MRI定量技术3D-IDEAL-IQ分析2型糖尿病(T2DM)患者与健康志愿者之间的大腿肌间、肌内脂肪浸润含量差异,并分析其分布情况。方法:搜集确诊为T2DM的男性患者23例,女性患者20例(T2DM组),招募年龄、性别相匹配的健康志愿者40例(对照组,男20例,女20例)。对所有受试者进行大腿中段的MRI检查,分别测量皮下脂肪面积和肌肉区域间脂肪面积,通过各肌肉脂肪分数计算肌肉内的脂肪面积及单纯肌肉面积。再根据人体解剖学分区将肌肉分群,分别计算各肌群的肌肉内脂肪面积及纯肌肉面积。结果:T2DM组的皮下脂肪面积(P=0.004)、肌肉区域间的脂肪面积(P<0.001)、肌内脂肪面积(P<0.001)绝对值均大于对照组;T2DM组的肌内脂肪面积相对值较对照组大(P<0.001),单纯肌肉面积相对值较对照组小(P=0.044),并且大腿前外侧群肌肉减少更为显著(P=0.003)。结论:3D-IDEAL-IQ定量技术可以用于评价T2DM患者大腿肌间和肌内脂肪浸润含量和分布;T2DM患者大腿骨骼肌的脂肪及肌肉的比率较健康人群产生变化,脂肪沉积更明显,肌肉含量更少,且...     

2型糖尿病骨骼肌改变的影像学研究进展

2型糖尿病(T2DM)是常见病、多发病, 骨骼肌胰岛素抵抗被认为是始动因素和关键环节。骨骼肌肌量减少和脂肪浸润与T2DM的病理过程密切相关。近年来, 多种影像技术在骨骼肌肌量减少与脂肪浸润的测定及其与T2DM可能的内在机制的研究不断取得新的成果。早期识别T2DM骨骼肌改变, 探究其与T2DM实验室检查指标的相关性, 对于制定T2DM治疗方案具有重要指导作用。     

胰腺脂肪浸润的CT诊断及临床相关性分析

目的:探讨胰腺脂肪浸润的CT诊断价值以及与高血糖、2型糖尿病、高血脂、脂肪肝以及高血压的相关性分析。方法:总结50例胰腺脂肪浸润患者的血糖、血脂值及脂肪肝、高血压的发生情况,设立对照组并与之对比分析。结果:50例胰腺脂肪浸润患者,患者的血糖升高37例、确诊2型糖尿病(T2DM)32例,血脂升高48例,高血压42例、脂肪肝50例。与对照组差别显著(P0.001)。结论:CT能够准确诊断胰腺和肝脏脂肪浸润;胰腺脂肪浸润与高血糖、2型糖尿病、高血压、高血脂、脂肪肝存在高度相关;研究结果能为该类患者临床诊断与治疗提供可靠的依据。     

CT平扫定量测量胰腺脂肪含量的临床应用价值

目的:评价手术切除胰腺标本脂肪含量与CT测量指标的相关性,并分析其用于评估临床糖代谢异常的价值。方法:回顾性分析78例行胰腺切除术并于术前1个月内接受CT检查患者的临床和影像学资料,其中男54例,女24例,年龄21~79岁,平均63.5岁。测量手术切除标本胰腺非肿瘤组织的胰腺脂肪含量,以视野中脂肪面积占整个视野面积百分比表示。在CT平扫图像上测量胰腺和脾的平均CT值,计算胰腺与脾CT值差值(P-S)及胰腺与脾CT值比值(P/S)。选择脐水平层面测量腹腔内脏脂肪面积。利用Spearman相关分析判断CT测量指标、内脏脂肪面积与组织标本胰腺脂肪含量的相关性;采用多变量Logistic回归模型确定CT测量指标、年龄、性别、内脏脂肪含量与糖代谢异常(如糖耐量受损、空腹血糖异常或糖尿病)的相关性。结果:组织病理学上胰腺脂肪含量为0~68.4%,与P-S、P/S显著相关(均P0.01)。内脏脂肪面积与胰腺脂肪含量无显著相关性(P=0.52)。在年龄、性别和内脏脂肪面积调整后,CT测量指标仍是预测糖代谢受损的显著性独立影响因素。结论:CT可定量测量胰腺脂肪含量,CT值量化的胰腺脂肪含量化与糖代谢异常显著相关。     

多模式MRI与2型糖尿病患者脂肪代谢标志物的相关性分析

目的：利用双回波同反相位技术（DEI）、磁共振波谱技术（MRS）等方法评价2型糖尿病（T2DM）患者脂肪组织分布,并探讨其影响因素。方法对58例T2 DM 患者进行人体学特征、血生化指标检测及磁共振扫描,测量肝脏脂肪含量、骨骼肌细胞内、外脂肪含量、腹壁皮下脂肪面积、腹腔内脂肪面积及腹部脂肪总面积。将不同部位脂肪含量进行单因素和多因素回归分析。结果餐后2h血糖（2hPPG）、腹腔内脂肪面积（VAT）、腹部脂肪总面积（TA）、肝脏脂肪变指数（HFF）、肝脏相对脂肪含量（RLC）在是否合并脂肪肝组间有明显差异（ P ＜0．05）,身体质量指数（BMI）与脂肪面积指标（VAT、SAT、TA）及肝脏脂肪含量指标（HFF、RLC）呈明显正相关（ P ＜0．01）,且对脂肪面积指标（VAT、SAT、TA）有正向影响;2hPPG与VAT、TA呈正相关（ P ＜0．05）,2hPPG对VAT有正向影响,总胆固醇（TC）、低密度脂蛋白（LDL）与VAT、TA呈正相关（ P ＜0．05）;丙氨酸转氨酶（ALT）与HFF、RLC呈正相关。结论对于 T2DM 患者应积极预防、治疗脂肪肝,磁共振能更好的检测异位脂质。     

胰腺脂肪定量的CT和MRI研究进展

近年来,越来越多的研究证实胰腺脂肪浸润与肥胖、高血压、糖尿病、高血脂以及胰腺癌、胰腺癌淋巴结转移、术后胰瘘等疾病有关。胰腺脂肪定量对这些相关疾病的预防、早期诊断、治疗、疗效评价以及预后评估等都具有重要的临床价值。CT和MRI是准确、安全、快速地诊断和定量成人及儿童胰腺脂肪浸润的影像方法。就胰腺脂肪浸润的影像诊断及胰腺脂肪定量的CT和MRI研究进展予以综述。     

T2-mapping和化学位移成像定量观察正常成人多裂肌内少量脂肪的价值

【摘要】目的：探讨T2-mapping和磁共振化学位移成像（CSI）定量观察健康志愿者多裂肌内少量脂肪含量的价值。方法：对56名健康志愿者（年龄22~59岁）进行腰椎常规MRI检查及T2-mapping和CSI。根据Goutallier分级系统，在常规MRI图像上进行脂肪浸润分级。用T2-mapping非抑脂序列图像测得的T2值（非抑脂）减去抑脂序列测得的T2值（抑脂）得到T2值（脂肪）。CSI采用非对称回波的最小二程估算法迭代水脂分离(IDEAL)技术，并在IDEAL图像上计算得到脂肪分数η。采用多元回归分析和pearson相关分析评价年龄、性别、身高体重指数（BMI）与T2值（非抑脂）、T2值（脂肪）和脂肪分数η的相关性。结果：56名志愿者的平均T2值（脂肪）为（6.1±1.58）ms（95%置信区间：5.7ms，6.6ms）；T2值（非抑脂）为（44.9±4.66）ms（95%置信区间：43.8ms，46.2ms）。T2值（脂肪）与年龄、BMI均具有相关性（P均＜0.001），脂肪分数η与年龄、BMI亦具有相关性（P均＜0.05），T2值（脂肪）与脂肪分数η呈显著相关性（r=0.794，P＜0.001）。结论：T2-mapping和CSI能识别正常成人肌肉内少量脂肪的差异，所测参数显示出与健康志愿者体格特征的相关性。     

磁共振波谱成像评估初发2型糖尿病患者骨髓脂肪含量

目的探讨磁共振波谱成像(MRS)定量评估初发2型糖尿病(T2DM)骨髓脂肪含量变化及其与胰岛素抵抗的相关性。方法初发T2DM患者及年龄匹配的正常对照组(n=32/组)行双能X线骨密度测定及股骨颈MRS扫描,分别获得骨密度(BMD)及骨髓脂肪分数(FF)。检查2组研究对象空腹血糖(FPG)、糖化血红蛋白(Hb A1c)、胰岛素(FINS)及血脂指标(TC、TG、HDL-C、LDL-C),利用稳态模式评估法评价胰岛素抵抗(HOMA-IR)。结果初发T2DM组BMD值与对照组无统计学差异。初发T2DM组FF值显著高于正常对照组(P0.001),校正糖代谢、脂代谢及BMD值,2组间FF值仍存在统计学差异(F值=16.763,P=0.012)。FF与HOMA-IR呈中度正相关性(r=0.683,P0.001),校正BMI,FF与HOMA-IR仍然存在正相关性(r=0.592,P=0.018)。结论初发T2DM患者骨髓脂肪增高,骨髓脂肪增多可能是胰岛素抵抗的影响因素之一。     

绝经后新诊断2型糖尿病腰椎骨髓脂肪成分的MRS测定

目的探讨磁共振波谱成像(MRS)用于定量绝经后新诊断2型糖尿病(T2DM)病人骨髓脂肪成分的变化,并分析其与糖化血红蛋白(HbA1C)的相关性。方法收集25例绝经后新诊断T2DM女性病人,年龄(57.4±4.5)岁,以25例健康女性作为对照者,年龄(56.6±4.0)岁。两组均行腰3椎体1H-MRS扫描,计算骨髓脂肪含量(FC)及不饱和脂肪指数(UFI)。测定被检者空腹血糖及HbA1C。采用独立样本t检验比较组间年龄、体质量指数(BMI)、血糖、HbA1C、FC及UFI差异,采用Pearson相关分析两组的FC、UFI与血糖及HbA1C的相关性。结果T2DM组骨髓FC值(63.2%±7.4%)与正常对照组(60.9%±6.9%)差异无统计学意义,但T2DM组骨髓UFI(6.1%±0.8%)较正常对照组(7.6%±0.9%)降低(t=-3.775,P0.001)。T2DM组HbA1C7.0%者的骨髓FC(66.0%±6.3%)高于HbA1C≤7.0%者(57.6%±6.5%)(t=2.893,P0.001)。T2DM组骨髓FC与HbA1C呈高度正相关(r=0.801,P0.001),而骨髓UFI与HbA1C水平呈负相关(r=-0.746,P0.001),但FC(r=0.226,P=0.206)和UFI(r=-0.184,P=0.589)与血糖无相关性。结论 T2DM病人腰椎骨髓FC可无明显变化,但UFI明显降低。T2DM骨髓脂肪成分与HbA1C密切相关,MRS测定骨髓脂肪组分可看作血糖控制程度的标志。     

内脏脂肪与2型糖尿病血管并发症的关系研究进展

2型糖尿病(T2DM)血管并发症包括大血管并发症和微血管并发症,其发病率的升高往往伴随着高肥胖发生率。肥胖是T2DM的独立危险因素。研究显示,体脂分布而不是体脂总量与肥胖患者的代谢及心血管风险相关。体重指数(BMI)和腰围(WC)不能准确地反映肥胖患者的体脂分布情况,因此,内脏脂肪越来越受重视,并可能成为T2DM血管并发症的预测指标。本文就内脏脂肪与T2DM血管并发症的相关性及其作用机制研究进展进行综述,以期为内脏脂肪的深入研究和临床检查提供参考。     

Quantification of pancreatic lipomatosis and liver steatosis by MRI: comparison of in/opposed-phase and spectral-spatial excitation techniques

OBJECTIVES: The goal of the present study was the assessment of pancreatic and hepatic fat content applying 2 established magnetic resonance (MR) imaging techniques: in-phase/opposed-phase gradient-echo MR imaging and fat-selective spectral-spatial gradient-echo imaging. Results of both approaches were compared, and influences of T1- and T2*-related corrections were assessed. The possibility of a correlation between pancreatic lipomatosis and liver steatosis was investigated. MATERIALS AND METHODS: Seventeen volunteers at risk for type 2 diabetes (6 male, 11 female; age, 26-70 years; body mass index, 19.4-41.3 kg/m2; mean, 31.7 kg/m2) were examined. Liver and pancreas fat content were quantified with 2 different gradient-echo techniques: one uses a spectral-spatial excitation technique with 6 binomial radio frequency pulses, which combines chemical shift selectivity with simultaneous slice-selective excitation. The other technique based on double-echo chemical shift gradient-echo MR provides in- and opposed-phase images simultaneously. Influences of T1 and individual T2* effects on results using in-phase/opposed-phase imaging were estimated and corrected for, based on additional T2* measurements. RESULTS: The fat content calculated from images recorded with the fat-selective spectral-spatial gradient-echo sequence correlated well with the fat fraction determined with in-phase/opposed-phase imaging and following correction for T1/T2* effects: pancreas r = 0.93 (P < 0.0001) and liver r = 0.96 (P < 0.0001). In-phase/opposed-phase imaging revealed a pancreatic fat content between 1.6% and 22.2% (mean, 8.8% +/- 5.7%) and a hepatic fat fraction between 0.6% and 33.3% (mean, 7.9% +/- 9.1%). The fat-selective spectral-spatial gradient-echo sequence revealed a pancreatic lipid content between 3.4% and 16.1% (mean, 9.8% +/- 4.0%) and a hepatic fat content between 0% and 28.5% (mean, 8.8% +/- 8.3%). With neither technique was a substantial correlation between pancreatic and hepatic fat content found. CONCLUSION: The presented results suggest that both methods are reliable tools for pancreatic and hepatic fat quantification. However, for reliable assessment of quantitative fat by the in-phase/opposed-phase technique, an additional measurement of T2* seems crucial.     

Evaluation of the pancreas by MRI

Using T1-, P- and T2-weighted images of the upper abdomen obtained on 1.5 T MRI system, 18 items on the pancreas were evaluated in 89 controls. The items included pancreas sizes on T1-weighted image. pancreatic intensity compared with those of renal cortex, subcutaneous fat tissue, liver and spleen, obliteration of pancreas margin, and diameter of pancreatic duct on all images. Normal criteria, which were determined from data in the controls, were applied to images in the 40 patients with pancreatic or peripancreaticdiseases. All 4 patients with an extra-pancrcatic tumor had no abnormality of pancreatic intensity. pancreatic margin, and pancreatic duct on T2-weighted image, except for pancreatic sizes and intensities at tumor sites. In contrast. 34 of 36 patients with pancreatic disease had abnormalities which pathologically depended on acute and/or chronic pancreatitis.     

Computed tomography of peripancreatic fat planes

Obliteration of peripancreatic fat planes usually is considered an indicator of peripancreatic tumour infiltration in the presence of a malignant mass, or of inflammation of peripancreatic tissues in patients with pancreatitis. However, absence of peripancreatic fat planes also may be found in patients without evidence of pancreatic disease. Hence, CT scans of 125 patients without clinical or computed tomographic evidence of pancreatic disease were evaluated to assess normal variations in the anatomy of the pancreas and its relation to surrounding vessels and bowel loops. The fat plane separating the superior mesenteric artery from the pancreas was preserved in 100% of patients. Conversely, fat planes between the pancreas and the superior mesenteric vein, inferior vena cava, and adjacent bowel loops were partially or totally obliterated in 13% to 50% of patients. It is concluded that the absence of fat around the superior mesenteric artery is highly suggestive of pathologic changes of the pancreas, while the lack of fat planes between the pancreas and other splanchnic vessels or bowel loops frequently is normal, and therefore, is an unreliable sign of pancreatic disease. The applications of these findings to the assessment of tumour resectability by CT, and to CT scanning techniques, are discussed.     

白血病胰腺浸润的影像学表现

目的:探讨白血病胰腺浸润的影像特征,为临床治疗提供参考信息。方法:回顾性分析经临床及病理证实的7例白血病胰腺浸润患者的CT和MRI表现,7例患者中4例行MRI平扫及增强扫描,1例行MRI平扫,2例行CT平扫及增强扫描。结果:5例累及胰头部,2例同时累及胰头和胰尾部。6例表现为肿块型,1例同时表现为弥漫型和肿块型;肿块型表现为类圆形、不规则状肿块;弥漫型表现为受累部位肿胀,与胰腺轮廓一样;2例肿块型伴远侧胰管扩张。2例CT上表现为等密度;5例MRI上表现为T₁WI呈等信号,T₂WI呈等或稍低信号,DWI呈高信号。6例增强扫描均表现为乏血供,强化程度明显低于胰腺。结论:白血病胰腺浸润的CT和MRI表现具有一定特征性,正确认识并诊断对临床治疗有重要作用。     

胰腺疾病的MRI诊断

随着MBI成像技术的迅速发展和MBI的广泛应用，利用MBI诊断胰腺疾病正引起人们的普遍关注。现代MRI技术包括屏气T1加权成像及其脂肪抑制、T2加权成像及其脂肪抑制、MBI动态增强扫描、MR胰胆管成像和MR血管成像。这些脉冲序列各自有不同的组织对比机制，而且是互相补充的，它们的综合应用，可以较全面地评价胰腺及胰腺病变，从而明显改善了MBI对胰腺疾病的检测和诊断。本文着重介绍胰腺的MR成像技术，正常解剖、先天性异常和常见疾病的NR诊断价值。     

3.0T磁共振弥散加权成像在胰腺癌中的应用价值

目的:分析评价在3.0T磁共振非脂肪抑制憋气DWl序列在胰腺癌中的应用价值.方法-30例正常志愿者与30例经手术病理证实的胰腺癌患者,在3.0T磁共振上,术前行基于SE-EPI的非脂肪抑制憋气DWI序列,b值为0和600s/mm2,统计学比较分析正常胰腺、胰腺癌及远端炎症区的ADC值.结果:不同组织的ADC值从低到高依次为胰腺癌、正常胰腺、远端炎症,单因素方差分析显示不同组织的ADC值有明显统计学差异,F值为18.716,P值为0.0004,两两比较分析显示胰腺癌分别与正常胰腺及远端炎症的ADC值统计学有明显差异,P值分别为0.00483及0.00191.结论:在3.0T磁共振上,非脂肪抑制憋气DWI序列有助于病灶筛查,其ADC值能够较好的反映胰腺癌、正常胰腺及远端炎症的组织病理状态.     

Lipoma of the pancreas: MRI findings

Lipomas of the pancreas are very rare. Focal fatty infiltration of the pancreas is an entity that should be differentiated from a pancreatic lipoma. In this report the MRI findings of an incidentally found pancreatic lipoma are presented and the role of MRI in the differentiation of pancreatic lipoma and focal fatty infiltration of the pancreas is discussed.     

Pancreatic carcinoma and fast MR imaging: technical considerations for signal intensity difference measurements

The aim of the study was to find the fast magnetic resonance imaging (MRI) sequence with the best conspicuity of pancreatic lesions at 1.0 T and 1.5 T. A total of 51 patients were studied. At 1.0 T, 22 patients with verified malignant pancreatic lesions were studied using the T1-weighted breath-hold spoiled Gradient Echo 2D FLASH(75) or FLASH(80) sequences, both non-enhanced and enhanced with gadolinium. The relative signal intensity difference (SIDR) between lesion and pancreas was measured. At 1.5 T, 20 patients with primary malignant lesions of the pancreas, and nine patients with 13 benign cystic lesions were examined with the breath-hold T2-weighted TrueFISP, HASTE, T1-weighted 2D FLASH(80) and FLASH(50) fat saturation sequences, the latter also enhanced. The signal intensity (SI) values of the pancreas and lesions as well as the pancreatic standard deviation (S.D.) were assessed, and the contrast-to-noise ratio (C/N) was determined. Statistical significances were calculated using an analysis of variance. No statistically significant difference between the sequences used in the conspicuity of cancer was found, either at 1.0 T or at 1.5 T. At 1.5 T, the T2-weighted TrueFISP and HASTE sequences could differentiate benign, cystic lesions from malignant lesions.