纹理分析在MRI动态增强扫描鉴别肾细胞癌亚型中的应用研究

目的探讨动态增强MRI三维纹理分析鉴别透明细胞肾细胞癌(clear cell renalcell carcinoma,ccRCC)、乳头状肾细胞癌(papillary renal cell carcinoma,pRCC)和嫌色肾细胞癌(chromophobe renal cell carcinoma,ChRCC)的价值。材料与方法回顾性分析经病理证实的74例ccRCC、22例pRCC和17例ChRCC患者资料,分别提取肾皮髓质期、实质期及延迟期增强T1WI上肿瘤三维纹理特征,筛选后应用原始数据分析、主成分分析、线性判别分析和非线性判别分析方法进行分类分析,计算诊断准确率、敏感度、特异度及受试者工作特征曲线下面积(area under the curve,AUC)。结果动态增强MRI三维纹理分析鉴别ccRCC与pRCC的诊断准确率、敏感度、特异度达88.54%、91.89%、77.27%(AUC=0.846);鉴别ccRCC与ChRCC的诊断准确率、敏感度、特异度达95.60%、97.30%、88.24%(AUC=0.928);鉴别pRCC与ChRCC的诊断准确率、敏感度、特异度达79.49%、72.73%、88.24%(AUC=0.805)。非线性判别分析方法均获得较高的诊断效能(AUC 0.707~0.928)。结论 DCE-MRI三维纹理分析有助于鉴别ccRCC、pRCC和ChRCC。     

CT三期动态增强扫描对早期肾透明细胞癌的诊断价值

目的:探讨早期肾透明细胞癌(renal clear cell carcinoma,ccRCC)诊断和鉴别诊断中应用CT多期动态增强扫描的临床价值。方法:收集并回顾分析本院收治的52例ccRCC患者的临床资料和影像学资料,比较分析52例ccRCC患者平扫、皮髓质期、肾实质期及排泄期Ⅰ～Ⅱ级ccRCC的强化程度及强化模式;并以手术或病理学活检结果为标准,比较CT平扫和CT三期动态增强扫描的诊断价值。结果:Ⅰ级和Ⅱ级ccRCC的平扫CT值差异无统计学意义(P0.05)。增强扫描皮髓质期、肾实质期及排泄期,Ⅱ级ccRCC的CT值(Hu)均高于Ⅰ级ccRCC(均P0.05)。Ⅰ级ccRCC均匀强化相对更常见,Ⅱ级ccRCC不均匀强化相对更常见。此外,CT平扫准确诊断患者例数为39例,准确诊断率为75%,明显低于三期动态增强扫描98.08%(51/58),差异具有统计学意义(P0.05)。结论:螺旋CT三期动态增强扫描对于早期ccRCC的分期鉴别有应用价值,Ⅰ级与Ⅱ级ccRCC在强化程度和强化模式上差异均有统计学意义,其可用于辅助进行术前分期及治疗方案选择。相较CT平扫,CT三期动态增强扫描对ccRCC的准确诊断率更高。     

双源CT碘定量技术评价肾透明细胞癌病理分级

目的:探讨双源CT碘定量技术在术前评估肾透明细胞癌(ccRCC)病理分级中的应用价值。方法:回顾性分析32例经手术病理证实并行双能量模式增强扫描的ccRCC患者的影像资料,利用双能量软件处理得到碘图,对高低级别组ccRCC标准碘浓度(NIC)进行比较研究。结果:低级别组19例,高级别组13例。皮髓期及实质期低级别组ccRCC的NIC均高于高级别组,差异具有统计学意义(P<0.05)。结论:双源CT碘定量技术有助于评估ccRCC的病理分级。     

肾透明细胞癌与肾嗜酸性细胞腺瘤的MRI纹理分析与鉴别

目的 探究磁共振成像(magnetic resonance imaging,MRI)纹理分析在肾透明细胞癌(clear-cell renal cell carcinomas,ccRCC)与肾嗜酸性细胞腺瘤(renal oncocytoma,RO)中鉴别价值.材料与方法 对2012年5月至2019年11月期间收治的42例ccRCC与15例RO患者资料予以回顾性分析,分别作为ccRCC组与RO组,患者接受MRI常规扫描与增强扫描后行纹理扫描分析.ccRCC与RO鉴别三维纹理特征选择频率,MRI纹理分析鉴别ccRCC与RO诊断效能,ccRCC与RO患者COM纹理参数比较,COM纹理参数在ccRCC与RO患者鉴别上价值分析.结果 ccRCC与RO鉴别所筛选纹理特征多来自共生矩阵(co occurrence matrix,COM),ccRCC与RO鉴别中肾实质增强T1加权成像(T1 weighted imaging,T1WI)序列筛选出层间纹理特征最多;通过非线性判别分析方法 进行MRI纹理分析来鉴别ccRCC与RO,在肾实质期增强纹理特征诊断效能最佳,诊断敏感度、特异度以及准确度分别为92.86％、73.33％以及87.72％;ccRCC组患者T1WI增强COM纹理参数如熵、逆差距以及相关显著低于RO患者(P<0.05),而对比与能量差异无统计学意义(P>0.05);受试者工作特征(receiver operating characteristic,ROC)曲线应用COM纹理参数熵、逆差距、相关鉴别ccRCC与RO患者曲线下面积(area under curve,AUC)分别为0.883、0.752、0.806,熵在鉴别ccRCC与RO患者价值最佳,敏感度与特异度分别为88.5％和83.6％.结论 MRI纹理分析尤其是COM可以有效鉴别出ccRCC与RO.     

CT多期动态增强扫描在肾透明细胞癌术前诊断中的应用价值

目的:分析CT多期动态增强扫描在肾透明细胞癌(KIRC)术前诊断中的临床应用。方法:2019年6月至2022年1月于本院就诊的65例术前怀疑KIRC的病例，经术后病理确诊(金标准)为KIRC51例、非KIRC14例，同时收集所有病例的临床资料，以病理结果为金标准，鉴别CT多期动态增强扫描对KIRC及其Fuhrman分级诊断价值，对比分析其平扫、皮髓质期、实质期及延迟期KIRC的CT值。结果:KIRC患者与非KIRC患者的病灶大小、病灶单发或多发、坏死、囊变及强化分布有统计学意义(P<0.05);CT多期动态增强扫描诊断KIRC的敏感度94.12%、特异度71.43%、准确率89.23%、阳性预测值92.31%、阴性预测值76.92%、kappa值0.673;KIRC患者中Fuhrman分级高级别患者皮髓质期、实质期及延迟期强化CT值显著高于低级别(P<0.05);CT多期动态增强扫描鉴别高级别KIRC的敏感度88.57%、特异度87.5%、准确率88.24%、阳性预测值93.94%、阴性预测值77.78%、kappa值0.735。结论:CT多期动态增强扫描用于KIRC术前诊...     

MDCT肿瘤强化指数在微脂性肾血管平滑肌脂肪瘤、透明细胞癌鉴别诊断中的价值

目的：评价MDCT肿瘤强化指数在微脂性肾血管平滑肌脂肪瘤（RAML）、透明细胞癌（ccRCC）鉴别诊断中的价值。材料与方法：回顾分析温州医学院附属第一医院2006年7月~2009年7月手术病理证实21例微脂性RAML（平均最大径4.69cm）、52例ccRCC（平均最大径4.57cm）影像资料,测量感兴趣区（ROI,包括肿瘤及正常肾皮质）平扫、三期增强（皮髓质期、肾实质期、分泌期）CT值,计算肿瘤相对肾皮质强化指数（R）,R=病灶（CTpost-CTpre）/皮质（CTpost-CTpre）（其中CTpost为感兴趣区强化后CT值,CTpre为感兴趣区平扫CT值）。两组肾肿瘤患者性别比较采用卡方检验;患者年龄、肿瘤CT值、肿瘤相对强化指数采用两独立样本t检验;并应用ROC曲线评价三期R值诊断性能。结果：微脂性RAML、ccRCC组患者性别、就诊年龄、平扫CT值差异有统计学意义（P<0.05）;两组肿瘤间皮髓质期、肾实质期、分泌期CT值差异无显著性（P>0.05）;ccRCC组三期肿瘤相对强化指数R值均明显高于微脂性RAML组（P<0.01）;以ccRCC为对象,三期R值ROC曲线下面积分别为0.719、0.767、0.748,肾实质期R值界限值为0.4649,其敏感度71.2%,特异度81%;特异度为100%时,R值界限值为0.6296,此时敏感度44.2%。结论：MDCT肿瘤强化指数可用于鉴别微脂性RAML、ccRCC。     

磁共振T1、T2值在脑胶质瘤分级及细胞增殖活性预测中的临床价值

目的探讨磁共振平扫T1、T2值及增强后的T1值在脑胶质瘤分级及细胞增殖活性预测中的诊断价值。材料与方法回顾性分析手术病理证实的36例脑胶质瘤患者,其中高级别胶质瘤(high grade glioma,HGG)21例,低级别胶质瘤(low grade glioma,LGG)15例。所有患者在术前1周同时行多对比度一站式弛豫定量技术(magnetic resonance imaging compilation,Magic)扫描、Magic对比增强扫描。在增强前后生成的T1 mapping、T2 mapping测量肿瘤实质区、对侧镜像部位正常脑白质的增强前T1值(T1-pre)、T2值(T2-pre)及增强后T1值(T1-Gd)。对手术标本进行病理分级及Ki-67标记指数(Ki-67 LI)的测定。分析各项Magic参数及Ki-67 LI之间的相关性及高低级别组间Magic参数值、Ki-67 LI之间的差别,并绘制ROC曲线。结果T1-pre、增强前T1比值(ratio of T1-pre,rT1-pre)、T1-Gd、增强前后T1差值(ΔT1)、T1值变化百分比均与Ki-67 LI具有显著相关性(P<0.05),相关系数r分别为0.502、0.331、-0.351、0.537、0.473。高级别组胶质瘤T1-pre、ΔT1、T1值变化百分比、Ki-67 LI明显高于低级别组,T1-Gd、增强后T1比值(ratio of T1-Gd,rT1-Gd)低于低级别组,差异均具有统计学意义(P<0.05)。ΔT1对区分高、低级别胶质瘤的效能最好,其最佳诊断阈值373.25 ms,曲线下面积0.816,敏感度90.5%,特异度60%,P=0.001。结论定量测量T1值可用于鉴别高低级别胶质瘤,对预测肿瘤细胞增殖有一定的临床价值。     

肾透明细胞癌64排多层螺旋CT直接征象与病理学分级的对比研究

目的:探讨肾透明细胞癌(clear cell renal cell carcinoma,CCRCC)64排多层螺旋CT直接征象与病理学分级之间的相关性,并进行对比分析。方法:收集2015年2月—2018年5月期间安徽省黄山市人民医院经手术切除后病理学检查证实为CCRCC的34例患者,分析其术前64排多层螺旋CT平扫及多期增强扫描图像。CCRCC的直接征象包括肿瘤形态、大小、密度、强化方式、强化程度及是否有假包膜等,并与术后病理学分级进行对比。根据世界卫生组织(World Health Organization,WHO)/国际泌尿病理学会(International Society of Urological Pathology,ISUP)病理学分级标准,将CCRCC分为Ⅰ～Ⅳ级,其中Ⅰ～Ⅱ级定义为低级别组(n=28),Ⅲ～Ⅳ级定义为高级别组(n=6),采集相关数据,进行分析。结果:与低级别组CCRCC相比,高级别组CCRCC病灶形状更不规则(高级别组中不规则形肿块3例,占50.0%;低级别组中不规则肿块2例,占7.1%);平扫时肿瘤密度更高(高级别组中5例呈稍高密度,占83.3%;低级别组中仅3例呈稍高密度,占10.7%);增强扫描皮髓交界期肿瘤强化程度较弱[高级别组强化值与同侧正常肾皮质强化值平均差为(-16.1±12.3)HU,低级别组强化值与同侧正常肾皮质强化值平均差为(7.0±7.5)HU];实质期强化衰减程度较低[高级别组肿瘤平均强化衰减值为(-7.7±5.4)HU,低级别组肿瘤平均强化衰减值为(-17.3±7.3)HU]。两组间差异有统计学意义(P0.05)。结论:CCRCC的64排多层螺旋CT直接征象中,肿瘤形态、平扫密度、皮髓交界期肿瘤强化程度及实质期肿瘤强化减退程度等对判断其WHO/ISUP病理学分级具有一定价值,能为术前确定CCRCC治疗方案提供帮助。     

DWI多b值水通道蛋白分子成像在脑星形细胞瘤分级诊断的初步研究

目的探讨DWI多b值水通道蛋白分子成像在脑星形细胞瘤分级诊断的价值。材料与方法搜集经手术病理证实的52例脑星形细胞瘤患者,术前均行常规MRI扫描及多b值DWI扫描,其中低级别组(WHOⅠ~Ⅱ级)24例,高级别组(WHOⅢ~Ⅳ级)28例。测量肿瘤实质区的AQP-ADC值、常规ADC值。采用独立样本t检验分析AQP-ADC值、常规ADC值在高低级别脑星形细胞瘤中是否具有统计学差异,ROC曲线分析比较AQP-ADC值与常规ADC值的诊断效能。结果高级别组肿瘤实质区的AQP-ADC值高于低级别组,高级别组肿瘤实质区的常规ADC值明显低于低级别组;肿瘤实质区AQP-ADC值、常规ADC值在脑星形细胞瘤高低级别间有明显的统计学差异(P0.01),AQP-ADC值、常规ADC值对脑星形细胞瘤分级的ROC曲线下面积:AQP-ADC值为0.891,常规ADC值为0.778。结论 AQP-ADC值可以鉴别高低级别脑星形细胞瘤,且优于常规ADC值。     

3.0T MR体素内不相干运动成像、弥散张量成像及T1 mapping检测健康成年人肾功能

目的 观察3.0T MR体素内不相干运动成像(IVIM)、弥散张量成像(DTI)及T1 mapping技术检测健康成年人肾功能的价值。方法 对前瞻性招募的22名健康成年志愿者行3.0T MR肾脏IVIM、DTI及T1 mapping扫描,获得左、右肾皮髓质MRI参数,包括IVIM相关参数纯水分子扩散系数(D)、灌注相关扩散系数(D^*)和灌注分数(f)、DTI相关参数各向异性分数(FA)及T1 mapping相关参数T1值;观察肾脏不同部位各参数差异,评估其与估算肾小球滤过率(eGFR)的相关性,分析其反映肾功能的价值。结果 左、右肾皮髓质上、中、下份MRI参数及左、右肾MRI参数差异均无统计学意义(P均＞0.05)。双肾皮质表观弥散系数(ADC)及D均大于髓质,而FA及T1值均小于髓质(P均<0.05);双肾髓质T1值与eGFR中度相关(r=0.718,P=0.013)。观察者间双肾皮质及髓质ADC、D、FA及T1值测值的一致性良好(ICC=0.751~0.896,P均＜0.001),双肾皮质及髓质D^*、f的一致性一般(ICC=0.489~0.668,P均＜0.001)。结论 3.0T MR IVIM、DTI及T1 mapping技术有助于检测健康成年人肾功能。     

Role of MR texture analysis in histological subtyping and grading of renal cell carcinoma: a preliminary study

Purpose

The study evaluated the usefulness of magnetic resonance imaging (MRI) texture parameters in differentiating clear cell renal carcinoma (CC-RCC) from non-clear cell carcinoma (NC-RCC) and in the histological grading of CC-RCC.

Materials and methods

After institutional ethical approval, this retrospective study analyzed 33 patients with 34 RCC masses (29 CC-RCC and five NC-RCC; 19 low-grade and 10 high-grade CC-RCC), who underwent MRI between January 2011 and December 2012 on a 1.5-T scanner (Avanto, Siemens, Erlangen, Germany). The MRI protocol included T2-weighted imaging (T2WI), diffusion-weighted imaging [DWI; at b 0, 500 and 1000 s/mm² with apparent diffusion coefficient (ADC) maps] and T1-weighted pre and postcontrast [corticomedullary (CM) and nephrographic (NG) phase] acquisition. MR texture analysis (MRTA) was performed using the TexRAD research software (Feedback Medical Ltd., Cambridge, UK) by a single reader who placed free-hand polygonal region of interest (ROI) on the slice showing the maximum viable tumor. Filtration histogram-based texture analysis was used to generate six first-order statistical parameters [mean intensity, standard deviation (SD), mean of positive pixels (MPP), entropy, skewness and kurtosis] at five spatial scaling factors (SSF) as well as on the unfiltered image. Mann–Whitney test was used to compare the texture parameters of CC-RCC versus NC-RCC, and high-grade versus low-grade CC-RCC. P value < 0.05 was considered significant. A 3-step feature selection was used to obtain the best texture metrics for each MRI sequence and included the receiver-operating characteristic (ROC) curve analysis and Pearson’s correlation test.

Results

The best performing texture parameters in differentiating CC-RCC from NC-RCC for each sequence included (area under the curve in parentheses): entropy at SSF 4 (0.807) on T2WI, SD at SSF 4 (0.814) on DWI b500, SD at SSF 6 (0.879) on DWI b1000, mean at SSF 0 (0.848) on ADC, skewness at SSF 2 (0.854) on T1WI and skewness at SSF 3 (0.908) on CM phase. In differentiating high from low-grade CC-RCC, the best parameters were: entropy at SSF 6 (0.823) on DWI b1000, mean at SSF 3 (0.889) on CM phase and MPP at SSF 5 (0.870) on NG phase.

Conclusion

Several MR texture parameters showed excellent diagnostic performance (AUC > 0.8) in differentiating CC-RCC from NC-RCC, and high-grade from low-grade CC-RCC. MRTA could serve as a useful non-invasive tool for this purpose.

     

磁敏感成像与肾透明细胞癌病理分级的相关性研究

目的：评价磁敏感成像技术(SWI)划分透明细胞肾癌(CRCC)病理级别的可行性并比较SWI和坏死划分CRCC级别的能力。材料与方法回顾性分析35例病理证实的CRCC患者。所有患者均行常规MRI和SWI检查。肿瘤内磁敏感信号强度(ITSS)分为出血和微血管。评价高低级别CRCC ITSS和瘤内坏死的差异。比较ITSS和坏死鉴别高低级别CRCC的价值。结果35例患者中有31例在SWI上显示ITSS。4例瘤内未见ITSS的患者均为低级别CRCC。低级别CRCC的ITSS平均分数(1.24±0.72)明显低于高级别CRCC (2.70±0.48)(P<0.01)。10例低级别CRCC未见明显坏死。高低级别CRCC之间瘤内坏死的发生有明显差异(P<0.05)。ITSS区分高低级别CRCC的敏感性、特异性、阳性和阴性预测值分别为70.0%、100%、100%和89.3%;坏死为100%、40.0%、40.0%和100%。结论 SWI可评价瘤内ITSS并在术前区分CRCC的病理级别。     

MSCT对肾脏嗜酸细胞腺瘤和透明细胞癌的鉴别诊断价值

目的:探讨多层螺旋CT(Multi-slice spiral computed tomography,MSCT)四期扫描对肾脏嗜酸细胞腺瘤(Renal oncocytoma,RO)和透明细胞癌(Clear-cell renal cell carcinomas,ccRCC)的鉴别诊断价值。方法:搜集因肾脏占位行肾脏CT平扫和三期增强扫描患者79例共80枚瘤灶,经术后病理证实RO 29例,ccRCC 50例,并回顾性分析两组病例的影像表现,采用SPSS 19.0软件对肿瘤CT值、校正CT值、皮质期与实质期CT差值及增强廓清率进行独立样本t检验分析。采用Fisher确切概率法对肿瘤部位、形态、平扫特点、强化程度、强化方式、皮质期与实质期强化CT值差异、节段增强反转等征象进行统计分析。结果:RO和ccRCC皮质期CT值、皮质期校正CT值、皮质期与实质期CT差值和增强廓清率差异有统计学意义(P<0.05),平扫、实质期、排泄期CT值校正CT值差异均无统计学意义(P>0.05)。中央星状低密度影、强化程度、强化均匀度、轮辐状强化、皮质期与实质期强化CT值差异及节段增强反转等征象差异有统计学意义(P<0.05),部位、形态、钙化,病灶周边絮状和条索状影等征象差异无统计学意义(P>0.05)。结论:在MSCT多期扫描表现中,皮质期CT值、皮质期校正CT值、皮质期与实质期CT差值和增强廓清率、中央星状低密度影、强化程度、强化均匀度、轮辐状强化、皮质期与实质期强化CT值差异及节段增强反转等征象对于RO、ccRCC二者的鉴别具有重要价值。     

Juxtatumoral perinephric fat analysis in clear cell renal cell carcinoma

Purpose

The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1–2) versus high-grade (ISUP 3–4) clear cell renal cell carcinoma (ccRCC).

Methods

In this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively.

Results

All methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75.

Conclusions

Our study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.

     

多层螺旋CT鉴别肾癌WHO病理类型的应用价值

目的：探讨多层螺旋CT鉴别不同类型肾癌的价值。方法：回顾性分析经病理证实的92例肾癌的CT表现，依据WHO病理分类包括透明细胞癌54例、乳头状癌25例、嫌色细胞癌13例。比较平扫、皮髓质期、肾实质期及排泄期各类肾癌的CT值及强化模式。结果：3种肾癌在平扫的CT值无统计学差异。在增强扫描皮髓质期、肾实质期及排泄期，透明细胞癌的CT值均高于乳头状癌和嫌色细胞癌，而后两者在增强各期均无统计学差异。均匀强化最常见于嫌色细胞癌，不均匀强化最常见于透明细胞癌。螺旋CT鉴别透明细胞癌与非透明细胞癌的准确性在皮髓质期、肾实质期、排泄期分别为93.5%、86.9%、81.5%。结论：多层螺旋CT鉴别透明细胞癌与非透明细胞癌有应用价值，但较难鉴别乳头状癌和嫌色细胞癌。     

Can diffusion-weighted magnetic resonance imaging of clear cell renal carcinoma predict low from high nuclear grade tumors

Objective

To assess the diagnostic performance of the apparent diffusion coefficient (ADC) in predicting the Fuhrman nuclear grading of clear cell renal cell carcinomas (ccRCC).

Materials and methods

A total of 129 patients who underwent partial and radical nephrectomies with pathology-proven ccRCC were retrospectively evaluated. Histopathological characteristics and nuclear grades were analyzed. In addition, conventional magnetic resonance imaging (MRI) features were assessed in consensus by two radiologists to discriminate nuclear grading. ADC values were obtained from a region of interest (ROI) measurement in the ADC maps calculated from diffusion-weighted imaging (DWI) using b values of 50, 500, and 800 s/mm². The threshold values for predicting and differentiating low-grade cancers (Fuhrman I–II) from high grade (Fuhrman III–IV) was obtained using binary logistic regression. The ADC cut-off value for differentiating low- and high-grade tumors was determined using classification analysis.

Results

Significant associations (P < 0.001) were found between nuclear grading, conventional MR features, and DWI. Hemorrhage, necrosis, perirenal fat invasion, enhancement homogeneity, and cystic component were identified as independent predictors of tumor grade. High-grade ccRCC had significantly lower mean ADC values compared to low-grade tumors. An ADC cut-off value of 1.6 × 10⁻³ mm²/s had an optimal predictive percentage of 65.5% for low-grade tumors above this threshold and 81% for high-grade ccRCC below this threshold. Overall predictive accuracy was 70.5%.

Conclusion

The addition of ADC values to a model based on MRI conventional features demonstrates increased sensitivity and high specificity improving the distinguishing accuracy between both high-grade and low-grade ccRCC.

     

肾脏嫌色细胞癌的CT诊断

目的探讨肾嫌色细胞癌（CRCC）的CT表现特征,旨在提高术前诊断水平。方法回顾性分析23例CRCC,14例行CT平扫及皮髓质期、实质期双期增强扫描,5例行平扫及实质期增强扫描,4例直接行皮髓质期、实质期双期增强扫描,观察病灶大小、形态、密度,分析CT增强扫描特点。结果共23个病灶,呈类圆形、椭圆形或轻度分叶状,边界清楚,平均最大径4．7em。12例病灶密度均匀;11例病灶密度不均匀,其中9例可见钙化,6例发生坏死囊变的肿瘤中有4例最大径超过8．4cm。平扫病灶cT值23-48HU;与平扫相比,皮髓质期cT值平均增加34HU,实质期CT值平均增加32HU;实质期与皮髓质期相比,8例表现为密度降低,CT值相差约4-23HU,11例呈持续强化,CT值差约1．13HU。结论CRCC的CT表现具有一定特征性,术前CT检查对肿瘤的定性诊断具有较高的参考价值。     

MRI定量参数鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别

目的 观察MRI定量参数鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别的价值。方法 回顾性分析经病理确诊或随访复查诊断的58例丘脑胶质瘤（高、低级别胶质瘤分别为21例及37例）及21例丘脑转移癌患者，均接受头部常规MR检查，其中20例高级别胶质瘤、28例低级别胶质瘤及5例转移癌接受¹H-MR波谱（MRS）检查。比较高、低级别胶质瘤及转移癌之间水肿指数（EI）、对比增强率（CER）的差异，以及高、低级别胶质瘤间代谢物比值的差异。针对单因素分析结果显示差异有统计学意义的定量参数绘制受试者工作特征（ROC）曲线，计算曲线下面积（AUC），评估其鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别的效能。结果 丘脑转移癌EI大于高、低级别胶质瘤（P均<0.05）；高级别胶质瘤及转移癌CER均大于低级别胶质瘤（P均<0.05）。丘脑高级别胶质瘤实质区胆碱复合物（Cho）/肌酸（Cr）高于低级别胶质瘤（P=0.01）。高、低级别胶质瘤及转移癌之间，其余定量参数差异均无统计学意义（P均>0.05）。EI鉴别丘脑转移癌与胶质瘤的AUC为0.656，CER及肿瘤实质区Cho/Cr鉴别高级别与低级别胶质瘤的AUC分别为0.801及0.775。结论 EI有助于鉴别丘脑胶质瘤与转移癌；CER及肿瘤实质区Cho/Cr可用于鉴别丘脑高、低级别胶质瘤。     

MR氧摄取分数成像在星形细胞瘤分级的应用研究

目的探究基于非对称自旋回波(ASE)序列的氧摄取分数成像(OEF imaging)定量测量胶质瘤氧摄取分数的可行性,评价相关定量指标在星形细胞瘤分级诊断中的诊断性能。材料与方法 32例经病理诊断为星形细胞瘤的患者,其中Ⅱ级16例、Ⅲ级5例、Ⅳ级11例。所有受试对象扫描前均获得书面知情同意,扫描序列包括横断面T1WI、T2WI、T2 FLAIR、增强T1WI、ASE-OEF扫描。通过在肿瘤实体区手动绘制感兴趣区的方式测量肿瘤氧摄取分数(OEF),并对肿瘤标本进行ki-67免疫组化染色。采用独立样本t检验和单因素方差分析(oneway ANOVA)评价OEF定量指标在高低级别胶质瘤中的差异并与传统的MRI比较,采用受试者工作特征曲线进行诊断性能评价,采用Pearson相关分析OEF与Ki-67标记指数之间的相关性。结果增强扫描中,16例低级别胶质瘤10例表现为不强化,6例强化;16例高级别胶质瘤中,仅有1例不强化,其余15例表现为不同程度强化,差异有统计学差异(P=0.002)。高级别胶质瘤OEF明显高于低级别组,差异具有统计学意义(17.00±2.47、20.46±2.98,P0.01)。观察者间一致性分析显示ICC=0.89,表明测量结果具有良好的一致性。Ki-67 LI在高低级别胶质瘤中分别为48±54.01、5.8±8.76,差异具有统计学意义(P=0.01);Pearson相关分析表明Ki-67 LI与OEF存在中等的相关性(r=0.406,P0.05)。依据有无强化诊断高低级别胶质瘤的曲线下面积(AUC)为0.781,敏感度和特异度分别为93.8%和62.5%;定量指标OEF的诊断效能优于增强扫描,AUC为0.852,当取阈值为19.55时有最大的诊断效能,敏感度和特异度分别为81.3%和87.5%。结论基于EPI技术采集非对称自旋回波(ASE)序列可用于无创性测量肿瘤组织氧摄取分数;定量指标OEF能良好的鉴别高低级别胶质瘤,且能一定程度上反映肿瘤的增殖活性,在胶质瘤诊疗中具有较大的潜在应用前景。