应用扩散加权成像双指数模型评价慢性肾脏病的初步研究

目的应用扩散加权成像(DWI)双指数模型计算肾脏皮髓质的纯扩散系数(ADCd)及灌注分数(Fp),并分析其在慢性肾脏病(CKD)患者评价中的应用价值。方法搜集临床确诊的52例CKD患者和27名健康志愿者,分别行0、50,0、100,0、500,0、1000(s/mm2)四组b值的DWI检查,根据体素内不相干运动(IVIM)的双指数模型计算肾脏皮髓质的ADCd和Fp值,分析CKD患者皮髓质ADCd、Fp值的变化规律及其与肾小球滤过率估算值(eG-FR)之间的相关性。结果正常对照组肾脏皮质ADCd值显著大于髓质(P<0.05)。正常对照组、CKD轻度损害组和中重度损害组之间的肾脏皮髓质ADCd值均存在显著性差异(正常对照组>CKD轻度损害组>CKD中重度损害组)(P<0.001),三组之间的肾脏皮髓质Fp值均存在显著性差异(正常对照组>CKD轻度损害组>CKD中重度损害组)(P<0.001)。CKD患者的皮髓质ADCd值、髓质Fp值与eGFR均呈正相关(P<0.05)。结论 DWI双指数模型能够得到反映肾脏真实水分子扩散运动及微循环灌注的指标,肾脏皮髓质ADCd值及髓质Fp值可以在一定程度上反映CKD患者的肾脏功能改变。     

Preliminary Study of Biexponential Model of Diffusion Weighted Imaging in Evaluation of Chronic Kidney Disease

目的 应用扩散加权成像(DWI)双指数模型计算肾脏皮髓质的纯扩散系数(ADCd)及灌注分数(Fp),并分析其在慢性肾脏病(CKD)患者评价中的应用价值.方法 搜集临床确诊的52例CKD患者和27名健康志愿者,分别行0、50,0、100,0、500,0、1000( s/mm2)四组b值的DWI检查,根据体素内不相干运动(IVIM)的双指数模型计算肾脏皮髓质的ADCd和Fp值,分析CKD患者皮髓质ADCd、Fp值的变化规律及其与肾小球滤过率估算值(eG-FR)之间的相关性.结果 正常对照组肾脏皮质ADCd值显著大于髓质(P＜0.05).正常对照组、CKD轻度损害组和中重度损害组之间的肾脏皮髓质ADCd值均存在显著性差异(正常对照组＞CKD轻度损害组＞CKD中重度损害组)(P＜0.001),三组之间的肾脏皮髓质Fp值均存在显著性差异(正常对照组＞CKD轻度损害组＞CKD中重度损害组)(P＜0.001).CKD患者的皮髓质ADCd值、髓质Fp值与eGFR均呈正相关(P＜0.05).结论 DWI双指数模型能够得到反映肾脏真实水分子扩散运动及微循环灌注的指标,肾脏皮髓质ADCd值及髓质Fp值可以在一定程度上反映CKD患者的肾脏功能改变.     

DTI在慢性肾脏病患者早期肾脏功能损害中的临床应用价值

目的:探讨3.0 T MRI DTI及扩散张量示踪成像(DTT)在评估慢性肾脏病(CKD)患者肾脏早期功能变化中的价值。方法:选择50例CKD患者及19例健康志愿者行DTI扫描(b=0、400、600 s/mm~2),检查前测量血肌酐值。采用Pearson相关分析检验DTI参数与肾小球滤过率(eGFR)的相关性;单因素方差分析检验部分各向异性(FA)值评价CKD患者临床分期的价值;ROC曲线分析FA值评价CKDⅠ期患者的意义。结果:CKD患者肾脏皮、髓质的FA及ADC值与eGFR均呈正相关关系(FA:皮质r=0.708,髓质r=0.684;ADC:皮质r=0.355,髓质r=0.380)。不同CKD分期FA值差异均有统计学意义(皮质F=26.038,髓质F=26.611,均P0.001)。CKDⅠ期FA值低于对照组(P0.05)。DTT能直观显示CKD患者肾脏微结构变化;CKD患者肾功能损害,髓质管状结构数量减少、过早中断;CKD越严重,DTT图像变化越显著。结论:DTI能评价CKD患者肾功能变化,尤其能反映Ⅰ期患者的肾脏损伤;DTT能显示肾脏微结构变化。     

正常成人肾脏磁共振扩散加权成像研究

目的 通过测量正常成人肾脏磁共振扩散加权成像(DWI)时的表观弥散系数(ADC)值,为肾脏病变患者在DWI成像时提供正常对照标准.资料与方法 20例健康志愿者均行MRI常规平扫及DWI成像,DWI成像时b值分别采用0s/mm2、200s/mm2、500s/mm2、800s/mm2、1000s/mm2.结果 不同b值下双侧肾脏皮髓质ADC值及双侧肾脏平均ADC值差异有统计学意义(F=57.863～240.324,P=0.000),双侧肾脏皮髓质ADC值及平均ADC值均高于肝、脾及胰腺ADC值.双侧肾脏皮质在不同b值下的ADC值均高于髓质,差异有统计学意义(t=8.436～20.281,P=0.000).左侧肾脏皮、髓质ADC值及平均ADC值在b=500s/mm2、b=800s/mm2及1000s/mm2时均高于右侧,差异有统计学意义(b=800s/mm2时t=2.023,P=0.048;其余P=0.000).b=200s/mm2时双侧肾脏皮、髓质ADC值及平均ADC值之间差异无统计学意义(t=1.739,P=0.098;t=0.704,P=0.490;t=-0.314,P=0.757).结论 正常成人肾脏ADC值在不同b值下有差异,双侧肾脏平均ADC值亦存在差异.     

DTI量化评估慢性肾脏病患者肾功能状态及损伤程度的价值

目的探讨扩散张量成像(diffusion tensor imaging,DTI)量化对慢性肾脏病(chronic kidney disease,CKD)患者肾功能状态及肾功能损伤程度的临床预测价值。方法选取本院诊治的轻度(1~2期)CKD患者43例为轻度组,中重度(3~5期)CKD患者45例为中重度组,同期体检健康者50例为健康对照组。比较三组DTI相关参数各向异性分数(fractional anisotropy,FA)及表观弥散系数(apparentdiffusion coefficient,ADC)水平与肾功能指标的相关性;评估DTI量化指标对CKD肾功能及肾损伤的预测价值。结果三组皮质和髓质ADC值与FA值水平比较差异有统计学意义(P<0.05)且皮质和髓质ADC、FA值对照组>轻度组>重度组。三组肾功能指标比较差异有统计学意义(P<0.05),Scr、24h-Upro水平对照组<轻度组<重度组,eGFR水平对照组>轻度组>重度组。相关分析显示,皮质和髓质的ADC和FA值与均Scr、24h-Upro呈负相关,与eGFR呈正相关(P<0.05)。ROC曲线显示,髓质FA预测中重度CKD具有一定准确性(AUC=0.852,敏感度、特异度为82.2%、79.8%)。结论DTI量化相关参数对CKD,患者肾功能状态及损伤程度具有重要的预测价值。     

扩散张量成像对慢性肾脏病早期肾损害的评价

【摘要】目的：探讨MR扩散张量成像（DTI）评价慢性肾脏病（CKD)早期肾损害的临床应用价值。方法：A组,健康对照组12例;B组CKD危险因素组,13例;C组 1～3期CKD患者18例。所有受试者均行1.5T MR DTI,测量各向异性分数（FA）和表观扩散系数（ADC）。搜集各组的临床指标：估算肾小球滤过率 (eGFR）和血清胱抑素C（CysC）、血肌酐(Scr）。分析三组间的DTI参数差异及其与临床指标的相关性。结果：A组、B组和C组肾脏皮质FA分别为0.18±0.04,0.17±0.03,0.16±0.03,髓质FA分别为0.37±0.04,0.34±0.06,0.30±0.03,差异有统计学意义（P＜0.05）。皮质ADC值分别为（2.38±0.19）×10-3mm2/s,（2.26±0.16）×10-3mm2/s,（2.17±0.24）×10-3mm2/s,差异有统计学意义（P＜0.05）。肾脏皮质FA、髓质FA与eGFR呈正相关（r=0.373、0.418,P<0.05）。髓质FA与CysC呈负相关（r=-0.427,P<0.05）。皮质ADC与eGFR呈正相关（r=0.401,P<0.05）。皮质ADC与Scr呈负相关（r=-0.388,P<0.05）。受试者操作特征（ROC）曲线分析,以髓质FA≤0.327为界值,诊断早期CKD的敏感度为78.57%,特异度为94.44%,曲线下面积（AUC）为0.891,诊断效能较好。皮质FA诊断CKD肾损害的效能一般,AUC为0.774。结论：肾脏DTI可以早期发现CKD患者和CKD危险因素患者的肾损害,髓质FA值诊断早期CKD的效能较高。     

健康成人肾脏不同部位的磁共振扩散加权成像研究

目的通过测量健康成人肾脏磁共振扩散加权成像（DWI）时的表观弥散系数（ADC）值,为肾脏病变患者在DWI检查时提供正常对照值标准。方法 20名无任何肾疾患的健康志愿者均经MRI常规平扫及DWI扫描,DWI扫描时扩散敏感系数b值分别采用0 s/mm2、200 s/mm2、500 s/mm2、800 s/mm2及1000 s/mm2。全部操作是采用EPI序列和呼吸门控软件进行的。结果不同b值下双侧肾脏不同部位皮、髓质ADC值差异有统计学意义,双侧肾脏不同部位皮质在不同b值下的ADC值均高于相应部位髓质,两者之间差异有统计学意义（P=0.000）。结论健康成人肾脏各不同部位的ADC值与b值相关,肾脏皮质ADC值高于相应部位的髓质。     

健康成年人肾脏不同部位的DTI研究

目的:探讨年龄、性别及肾脏不同部位对DTI测量指标的影响。方法:收集60例正常志愿者行MR DTI成像检查,男女性各占30例,年龄分三组(40岁以下)、(40-60岁)、(60岁以上),每组20例,比较不同性别、年龄段及肾脏部位对ADC值、FA值的影响。结果:肾实质与肾皮质、髓质的ADC值存在相关性(r=0.91和0.92,P<0.01);肾实质与肾皮质、髓质的FA值存在相关性(r=0.90和0.88,P<0.01);不同性别、年龄段之间肾实质ADC、FA值比较均不具有统计意义(P>0.05),但肾实质ADC值随年龄段的增大逐渐减小,FA值随年龄段增大而逐渐增大;肾脏皮、髓质的上、中、下极ADC值、FA值比较均不具有统计学意义(P>0.05),左右侧比较不具有统计学意义(P>0.05)。结论:研究正常人肾脏ADC、FA值的变化特点,为今后肾脏疾病的诊断和鉴别诊断提供科学可靠的依据。     

糖尿病性肾病:磁共振扩散加权成像b值优化及在分期中的应用价值

目的 探讨3. 0T MRI多b值DWI技术对糖尿病肾病(DN)分期诊断的最优b值及诊断效能。方法 选取临床确诊的55例糖尿病肾病患者(包括DN早期组34例和中晚期组21例)和60例健康志愿者(正常对照组)作为观察对象。采用3. 0T MRI对肾脏进行DWI扫描,b值选取0、50、100、300、500、800 s/mm2,定量测量各组肾脏皮质及髓质ADC值并进行统计学分析,观察各组肾脏皮髓质ADC值的差异,以ROC曲线评价ADC值的鉴别诊断价值。结果 各b值下正常对照组、DN早期组和DN中晚期组的皮质及髓质ADC值均依次减低(P 0. 05),当b值取800 s/mm2时,三组间两两比较差异最显著(P 0. 01)。b值取800 s/mm2,鉴别正常对照组和DN早期组时,髓质ADC值的诊断效能高于皮质,敏感度为71. 7%,特异度为69. 1%;鉴别DN早期组与DN中晚期组时,皮质ADC值的诊断效能高于髓质,敏感度为92. 5%,特异度为42. 6%,两者的最佳诊断阈值均为1. 905。结论 b值取800 s/mm2是DN分期诊断的最优b值;肾脏皮髓质ADC值对糖尿病肾病的分期鉴别具有一定的诊断效能。     

T1-mapping评估慢性肾病肾功能损伤的价值

【摘要】目的：探讨磁共振T1-mapping成像评估慢性肾脏病（CKD）肾功能损伤的应用价值。方法：招募60例CKD患者和20例健康志愿者（对照组）。检测CKD患者的血清肌酐值并计算估算肾小球滤过率（eGFR）。将CKD患者分为两组,轻度肾损伤组［eGFR≥60mL/(min·1.73m2)］31例和中重度肾损伤组［eGFR<60mL/(min·1.73m2)］ 29例。所有受试者行双肾T1-mapping检查,测量肾皮质和肾髓质的T1值。采用配对样本t检验分析各组中肾皮质与肾髓质T1值的差异,3组之间肾皮质和肾髓质T1值的比较采用单因素方差分析,CKD组肾皮质和肾髓质T1值与eGFR之间的相关性评估采用Spearman相关性分析,采用ROC曲线评估肾皮质和髓质T1值评估肾功能损伤程度的诊断效能。结果：对照组、轻度肾损伤组及中重度肾损伤组中肾髓质的T1值均明显高于肾皮质T1值（P均＜0.05）。三组之间肾皮质和肾髓质T1值的差异均有统计学意义（P＜0.01）。CKD患者eGFR与肾皮质T1值呈高度负相关（r=－0.773,P<0.01）,与肾髓质T1值呈中度负相关（r=-0.689,P<0.01）。鉴别对照组与轻度肾损伤时,肾髓质T1值的ROC曲线下面积大于肾皮质T1值（0.866 vs. 0.821）;肾髓质T1值的截断值为1505.2ms时,敏感度和特异度分别为83.9%和80.0%。鉴别中重度与轻度肾损伤时,肾皮质T1值的ROC曲线下面积大于肾髓质T1值（0.874 vs. 0.820）;当肾皮质T1值的截断值为1457.3ms时,敏感度和特异度分别为82.8%和83.9%。结论：T1-mapping技术对于评估CKD肾功能损伤具有一定的价值。     

Diffusion tensor imaging and tractography of the kidneys: assessment of chronic parenchymal diseases

Objective

To assess renal dysfunction in chronic kidney diseases using diffusion tensor imaging (DTI).

Methods

Forty-seven patients with impaired renal function (study group) and 17 patients without renal diseases (control group) were examined using DTI sequences. Cortical and medullary regions of interest (ROIs) were located to obtain the corresponding values of the apparent diffusion coefficient (ADC) and the fractional anisotropy (FA). The mean values of the ADC and FA, for each ROI site, were obtained in each group and were compared. Furthermore, the correlations between the diffusion parameters and the estimated glomerular filtration rate (eGFR) were determined.

Results

In both the normal and affected kidneys, we obtained the cortico-medullary difference of the ADC and the FA values. The FA value in the medulla was significantly lower (P?=?0.0149) in patients with renal function impairment as compared to patients with normal renal function. A direct correlation between DTI parameters and the eGFR was not found. Tractography visualised disruption of the regular arrangement of the tracts in patient with renal function alteration.

Conclusion

DTI could be a useful tool in the evaluation of chronic kidney disease and, in particular, the medullary FA value seems to be the main parameter for assessing renal damage.

Key Points

? Magnetic resonance diffusion tensor imaging (MRDTI) provides new information about renal problems. ? DTI allows non-invasive repeatable evaluation of the renal parenchyma, without contrast media. ? DTI could become useful in the management of chronic parenchymal disease. ? DTI seems more appropriate for renal evaluation than diffusion-weighted imaging.     

3T MR DW和BOLD对移植肾初步研究

目的:研究3.0T MR对移植肾DWI和BOLD成像的可行性.初步设定在3.0T MR上正常自体肾和正常移植肾的ADC值和R2*值范围.对比慢性移植肾病的ADC和R2*值,希望能无创性地加以鉴别.方法:对16例正常人及16例肾移植患者(8例为正常移植肾,8例慢性移植肾病)进行DWI和BOLD功能成像,在工作站上分别进行皮质和髓质ROI的定位,并记录ADC值和R2*值,对所得的结果进行统计学分析.结果:在3.0T MR上肾脏DWI和BOLD图像信噪比良好,能满足成像要求.自体肾和正常移植肾的皮髓质ADC值和R2*值的基线和变化范围均较以前报道的在1.5T上获得的高.慢性移植肾病的皮质ADC值、髓质R2*值及髓皮质R2*比值均较正常移植肾降低,并且有统计学意义.结论:3.0T MR扫描仪对肾脏DWI和BOLD功能成像是可行的,并且有利于对肾脏的功能研究,对慢性移植肾病的鉴别有一定帮助.     

慢性肾脏病肾组织FA值与a-SMA表达的相关性研究

目的 评价慢性肾脏病(CKD)患者肾实质各向异性分数(FA)值与肾组织a-SMA表达的相关性.方法 对33例CKD患者进行3.0T MR肾脏扫描,扫描序列包括MRI常规扫描及扩散张量成像(DTI).在FA图上分别测量双侧肾脏皮质及髓质的FA值.其中有24例患者进行了肾组织活检.免疫组织化学法检测肾活检标本中a-SMA蛋白的表达,计算每个视野内阳色染色区域的积分光密度值,其平均值用于统计学分析.分别对肾皮质及肾髓质的FA值与免疫组织化学a-SMA的积分光密度值的相关性进行Bivariate相关分析.结果 肾皮质FA值与a-SMA的积分光密度值之间呈显著负相关(P=0.001).肾髓质FA值与a-SMA的积分光密度值之间呈显著相关性(P=0.035).结论 MR DTI获得的FA值与肾组织a-SMA表达具有相关性.     

Diffusion tensor imaging in renal artery stenosis: a preliminary report

Objective:To investigate the diffusion properties in the kidneys affected by renal artery stenosis (RAS) using diffusion tensor imaging (DTI).Methods:In this prospective study, 35 patients with RAS and 15 patients without renal abnormalities were enrolled and examined using DTI. Cortical and medullary regions of interest (ROIs) were located to obtain the corresponding values of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA). The cortical and medullary ADC and FA were compared in the kidney affected by variable degrees of stenosis (RAS 50–75% and >75%) vs controls, using the one-way ANOVA and Student’s t-test. The Spearman correlation test was used to correlate the mean ADC and FA values in the cortex and medulla with the estimate glomerular filtration rate (eGFR).Results:For the controls, the ADC value was significantly (p = 0.03) higher in the cortex than in the medulla; the FA value was significantly (p = 0.001) higher in the medulla than in the cortex. Compared with the controls, a significant reduction in the cortical ADC was present with a RAS of 50–75% and >75% (p = 0.001 and 0.041, respectively); a significant reduction in the medullary FA was verified only for RAS >75% (p = 0.023). The Spearman correlation test did not show a statistically significant correlation between the cortical and medullary ADC and FA, and the eGFR.Conclusion:The alterations of the diffusional parameters caused by RAS can be detected by DTI and could be useful in the diagnostic evaluation of these patients.Advances in knowledge:1. Magnetic resonance DTI could provide useful information about renal involvement in RAS.2. Magnetic resonance DTI allows non-invasive repeatable evaluation of the renal parenchyma, without contrast media.     

多带宽DTI-IVIM技术评估肾移植术后早期移植肾功能受损的价值

目的 探讨多带宽扩散张量成像-体素内不相干运动(multiband DTI-IVIM)技术评估肾移植术后早期不同程度受损移植肾功能的价值。方法 前瞻性收集异体肾移植术后2~4周病人92例行常规MRI、multiband DTIIVIM MRI检查。根据估算肾小球滤过率(eGFR)将病人分为3组:组1,eGFR≥60 mL/(min·1.73 m^2)(45例);组2,30 mL/(min·1.73 m^2)≤eGFR<60 mL/(min·1.73 m^2)(27例);组3,e GFR<30 mL/(min·1.73 m^2)(20例)。测量移植肾皮髓质的表观扩散系数(ADC)、单纯扩散系数(ADCslow)、微循环灌注系数(ADCfast)、灌注分数(f)、各向异性分数(FA)。采用配对t检验分析比较皮髓质间各参数值差异;采用单因素方差分析比较组间各参数值的差异;采用Pearson相关分析研究移植肾各参数值与eGFR间的相关性以及皮髓质FA值与其他各参数值的相关性。结果 组1肾皮质FA值低于髓质,余参数值高于髓质(P<0.05),组2、组3的ADCslow、ADCfast值及组2的f值皮髓质间差异无统计学意义(P>0.05)。组2肾皮髓质ADC、ADCslow、皮质f值及髓质FA值均低于组1(P<0.05)。组3肾皮髓质ADC、髓质ADCslow及髓质FA值均低于组2(P<0.05)。组3肾皮髓质ADC、ADCslow、f值、皮质ADCfast值及髓质FA值均低于组1(P<0.05)。各参数中,髓质FA值对组1和组2、组2和组3、组1和组3鉴别诊断效能最高(AUC分别为0.855、0.831、0.983);联合DTI-IVIM参数鉴别各组的能力最高(AUC分别为0.954、0.885、1.000)。除髓质ADCfast值、f值及皮质FA值外,移植肾各参数值与eGFR均呈中度正相关(r值为0.333~0.707,P<0.05)。髓质FA值与皮髓质ADC值、皮髓质ADCslow值及髓质f值均呈中度正相关(r值为0.335~0.526,P<0.05)。结论 multiband DTI-IVIM联合DTI和IVIM技术,可以评估并鉴别移植术后早期不同功能状态的移植肾功能。     

Diffusion-weighted imaging in assessing renal pathology of chronic kidney disease: A preliminary clinical study

Objective

To investigate the clinical potential of diffusion-weighted imaging (DWI) in assessing renal pathology of chronic kidney disease (CKD).

Methods

Seventy-one CKD patients and twelve healthy volunteers were examined using DWI with prospective acquisition correction. Renal biopsy specimens from the CKD patients were scored based on the severity of renal pathology and to confirm pathology type. CKD patients were divided into three groups according to pathology scores: mild, moderate, or severe. The association between renal apparent diffusion coefficient (ADC) values and pathology scores was investigated using Pearson's correlation and single factor analysis of variance. Multiple linear regression analysis was performed to explore associations between renal ADC values and pathology score, glomerular filtration rate, serum creatinine, and age. The Kruskal–Wallis H test was conducted to compare ADC values and pathology type.

Results

Renal ADC values correlated negatively with pathology scores (r = −0.633, P < 0.001). The ADC values among the four groups (mild, moderate, severe impairment, and controls) were significantly different (F = 19.512, P < 0.001). However, when patients were stratified by pathology type, no significant differences were found in ADC values among these groups (χ² = 9.929, P = 0.270). Further multiple linear regression analysis showed that only the pathology score and ADC values were related (t = −4.586, P = 0.000).

Conclusions

DWI has clinical potential in assessing the severity of renal pathology in CKD and shows promise as a non-invasive and effective technique to guide therapy and follow-up.     

Assessment of early renal allograft dysfunction with blood oxygenation level-dependent MRI and diffusion-weighted imaging

PurposeTo investigate blood oxygenation level-dependent (BOLD) MRI and diffusion-weighted imaging (DWI) at 3 T for assessment of early renal allograft dysfunction.Materials and methods34 patients with a renal allograft (early dysfunction, 24; normal, 10) were prospectively enrolled. BOLD MRI and DWI were performed at 3 T. R2* and apparent diffusion coefficient (ADC) values were measured in cortex and medulla of the allografts. Correlation between R2* or ADC values and estimated glomerular filtration rate (eGFR) was investigated. R2* or ADC values were compared among acute rejection (AR), acute tubular necrosis (ATN) and normal function.ResultsIn all renal allografts, cortical or medullary R2* and ADC values were moderately correlated with eGFR (P < 0.05). Early dysfunction group showed lower R2* and ADC values than normal function group (P < 0.05). AR or ATN had lower R2* values than normal allografts (P < 0.05), and ARs had lower cortical ADC values than normal allografts (P < 0.05). No significant difference of R2* or ADC values was found between AR and ATN (P > 0.05).ConclusionBOLD MRI and DWI at 3 T may demonstrate early functional state of renal allografts, but may be limited in characterizing a cause of early renal allograft dysfunction. Further studies are needed.     

Renal and perirenal space involvement in acute pancreatitis: An MRI study

Objectives

To study the prevalence and characteristics of renal and perirenal space involvement and its relation to the severity of acute pancreatitis (AP) using MRI.

Methods

115 patients with AP who underwent MRI with the clinical kidney function test were retrospectively analyzed in this study. MRI sequences included conventional and diffusion weighted imaging (DWI) sequences. The renal and perirenal space involvement in AP was noted on MRI. The renal apparent diffusion coefficient (ADC) on DWI was measured for each kidney. The severity of AP on MRI was graded using MR severity index (MRSI). The relationships among the renal and perirenal space involvement on MRI, the renal ADC, MRSI and the results of the kidney function test were analyzed.

Results

In the 115 patients with AP, the renal and perirenal space abnormalities detected included renal parenchymal abnormalities (0.8%), abnormalities of the renal collecting system (2.6%), renal vascular abnormalities (1.7%), thickened renal fascia (99%), perirenal stranding (62%) and perirenal fluid collection (40%). The prevalence of perirenal space abnormalities was correlated with the severity of AP based on MRSI (P < 0.05). The renal ADC values were lower in patients with abnormal kidney function than in those without kidney injury (P < 0.05). The prevalence of kidney function abnormalities was 9.4%, 32% and 100% in mild, moderate, and severe AP cases, respectively (P = 0.00).

Conclusion

Perirenal space involvement is much more than renal parenchymal involvement in AP. The prevalence of perirenal space involvement in AP on MRI has a positive correlation with the severity of AP according to MRSI.