Value of Apparent Diffusion Coefficient(ADC) of Diffusion eighted Magnetic Resonance Imaging in Common Renal Disease Diagnosis

Objective：To find the value of the apparent diffusion coefficient （ADC） of diffusion weighted magnetic resonance imaging of common renal diseases. Methods： There were 30 healthy subjects and 81 patients with renal lesions （56 cases of renal carcinoma, 18 lesions of 12 cases of renal angiomyolipomal and 21 lesions of 13 cases of renal cysts）. Conventional magnetic resonance imaging and diffusion weighted magnetic resonance imaging were carried out. We measured the average ADC value of the renal lesions and normal kidneys. ADC maps from different b values were generated by a statistical package. Results： The ADC values of normal kidneys with three different motion-probing gradients（b=500, 800, 1000 sec/mm^2） were 2.78 ± 0.14 × 10^-3mm^2s^-1, 2.45 ± 0.13 × 10^3mm^2s^-1, 2.13 ± 0.14 × 10^-3mm^2s^-1, respectively. The ADC values of renal cell carcinoma with three different motion-probing gradients（b=500, 800, 1000 sec/mm^2） were 1.63 ± 0.14 × 10^3mm^2s^-1, 1.31 ± 0.18 × 10^3mm^2s^-, 1.07 ± 0.15 × 10^-3mm^2s^-1, respectively. Among the renal cell carcinoma, the ADC value of clear cell type were 1.67 ± 0.09 × 10^3mm^2s^-1, 1.36 ± 0.13 × 10^3mm^2s^-1, 1.15 ± 0.14 × 10^3mm^2s^-1,respectively; the ADC values of granular cell type were 1.59±0.19 × 10^3mm^2s^-1, 1.25 ± 0.22 × 10^3mm^2s^-1, 0.97 ± 0.12 × 10^3mm^2s^-1, respectively. The ADC values of renal angiomyolipoma with three different motion-probing gradients（b=500, 800,1000 sec/mm^2） were 0.88 ± 0.08 × 10^3mm^2s^-1, 0.63 ± 0.07 × 10^3mm^2s^-1, 0.43 ± 0.04 × 10^3mm^2s^-1, respectively. The ADC values of renal cystic lesions with three different motionprobing gradients（b=500, 800, 1000 sec/mm^2） were 3.73 ± 0.18 × 10^3mm^2s^-1, 3.44 ± 0.13 × 10^3mm^2s^-1, 3.09± 0.21 × 10^3mm^2s^-1, respectively. Statistically significant differences exists between the ADC values of normal kidney, renal carcinomas, renal angiomyolipomas and renal cysts when the b value is the same. Among the different cell types of renal carcinomas, the ADC value of granular cell carcinoma is lower than that of clear cell carcinomas. Conclusion： It is of benefit in diagnosing and distinguishing between benign and malignant renal tumors to know the ADC values in diffusion weighted magnetic resonance imaging. Furthermore, these values help to know the internal structure of the tumor and the tumor typel, which is helpful to the treatment and in predicting the patient＇ s prognosis.

瘤周最大ADC联合T2WI影像征象对淋巴结阴性浸润性乳腺癌脉管侵犯的预测价值

目的探讨瘤周最大表观扩散系数(ADC)联合T2WI影像征象对淋巴结阴性浸润性乳腺癌脉管侵犯(LVI)的预测价值。方法收集150例淋巴结阴性浸润性乳腺癌患者,按术后LVI状态分为LVI+组25例,LVI-组125例,获得两组临床资料及MRI影像表现。采用χ^(2)/t检验对两组数据进行统计学分析,对两组有统计学差异变量绘制ROC曲线,分析其诊断效能。利用二元Logsitic回归选择与LVI相关变量建立模型,绘制ROC曲线评价此模型诊断效能。结果两组绝经史、组织学分级、雌激素受体(ER)、孕激素受体(PR)、人表皮生长因子受体2(Her-2)、Ki-67、雄激素受体(AR)、表皮生长因子(EGFR)、钙黏蛋白E(E-Cad)表达、分子亚型差异无统计学意义(P>0.05);两组肿瘤形状、边缘、内部强化特征、TIC、肿瘤最大径、早期强化率、峰值强化率、肿瘤ADC值差异无统计学意义(P>0.05);而瘤周水肿、瘤周最大ADC值差异有统计学意义(P<0.05);瘤周水肿、瘤周最大ADC值对LVI的AUC为0.672、0.762,二者联合的AUC为0.787。结论瘤周最大ADC、瘤周水肿对淋巴结阴性浸润性乳腺癌LVI的预测有一定的价值,前者的诊断效能优于后者,二者联合可提高诊断的特异度。

Apparent diffusion coefficient values of normal testis and variations with age

The usefulness of diffusion-weighted magnetic resonance imaging （DWI） in the evaluation of scrotal pathology has recently been reported. A standard reference of normal testicular apparent diffusion coefficient （ADC） values and their variations with age is necessary when interpreting normal testicular anatomy and pathology. We evaluated 147 normal testes using DWI, including 71 testes from 53 men aged 20-39years （group 1）, 67 testes from 42 men aged 40-69 years （group 2） and nine testes from six men older than 70years （group 3）. DWI was performed along the axial plane, using a single shot, multislice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s mm-2. The mean and standard deviation of the ADC values of normal testicular parenchyma were calculated for each age group separately. Analysis of variance （ANOVA） followed by post hoc analysis （Dunnett T3） was used for statistical purposes. The ADC values （x 10-3 mm2s-1） of normal testicular tissue were different among age groups （group 1：1.08 ± 0.13; group 2：1.15 ±0.15 and group 3：1.31± 0.22）. ANOVA revealed differences in mean ADC among age groups （F= 11.391, P〈 0.001）. Post hoc analysis showed differences between groups 1 and 2 （P= 0.008） and between groups 1 and 3 （P= 0.043）, but not between groups 2 and 3 （P= 0.197）. Our findings suggest that ADC values of normal testicular tissue increase with advancing age.

Apparent diffusion coefficient by diffusion-weighted magnetic resonance imaging as a sole biomarker for staging and prognosis of gastric cancer

Objective： To investigate the role of apparent diffusion coefficient （ADC） from diffusion-weighted magnetic resonance imaging （DW-MRI） when applied to the 7th TNM classification in the staging and prognosis of gastric cancer （GC）. Methods： Between October 2009 and May 2014, a total of 89 patients with non-metastatic, biopsy proven GC underwent 1.5T DW-MRI, and then treated with radical surgery. Tumor ADC was measured retrospectively and compared with final histology following the 7th TNM staging （local invasion, nodal involvement and according to the different groups -- stage Ⅰ, Ⅱ and Ⅲ）. Kaplan-Meier curves were also generated. The follow-up period is updated to May 2016. Results： Median follow-up period was 33 months and 45/89 （51%） deaths from GC were observed. ADC was significantly different both for local invasion and nodal involvement （P〈0.001）. Considering final histology as the reference standard, a preoperative ADC cut-offof 1.80×10-3 mm^2/s could distinguish between stages I and Ⅱ and an ADC value of ≤1.36-10-3 mm^2/s was associated with stage Ⅲ（P〈0.001）. Kaplan-Meier curves demonstrated that the survival rates for the three prognostic groups were significantly different according to final histology and ADC cut-offs （P〈0.001）. Conclusions： ADC is different according to local invasion, nodal involvement and the 7th TNM stage groups for GC, representing a potential, additional prognostic biomarker. The addition of DW-MRI could aid in the staging and risk stratification of GC.

Prediction of different stages of rectal cancer: Texture analysis based on diffusion-weighted images and apparent diffusion coefficient maps

BACKGROUND It is evident that an accurate evaluation of T and N stage rectal cancer is essential for treatment planning.It has not been extensively investigated whether texture features derived from diffusion-weighted imaging(DWI)images and apparent diffusion coefficient(ADC)maps are associated with the extent of local invasion(pathological stage T1-2 vs T3-4)and nodal involvement(pathological stage N0 vs N1-2)in rectal cancer.AIM To predict different stages of rectal cancer using texture analysis based on DWI images and ADC maps.METHODS One hundred and fifteen patients with pathologically proven rectal cancer,who underwent preoperative magnetic resonance imaging,including DWI,were enrolled,retrospectively.The ADC measurements(ADCmean,ADCmin,ADCmax)as well as texture features,including the gray level co-occurrence matrix parameters,the gray level run-length matrix parameters and wavelet parameters were calculated based on DWI(b=0 and b=1000)images and the ADC maps.Independent sample t-tests or Mann-Whitney U tests were used for statistical analysis.Multivariate logistic regression analysis was conducted to establish the models.The predictive performance was validated by receiver operating characteristic curve analysis.RESULTS Dissimilarity,sum average,information correlation and run-length nonuniformity from DWIb=0 images,gray level nonuniformity,run percentage and run-length nonuniformity from DWIb=1000 images,and dissimilarity and run percentage from ADC maps were found to be independent predictors of local invasion(stage T3-4).The area under the operating characteristic curve of the model reached 0.793 with a sensitivity of 78.57%and a specificity of 74.19%.Sum average,gray level nonuniformity and the horizontal components of symlet transform(SymletH)from DWIb=0 images,sum average,information correlation,long run low gray level emphasis and SymletH from DWIb=1000 images,and ADCmax,ADCmean and information correlation from ADC maps were identified as independent predictors of nodal involvement.The area under the operating characteristic curve of the model reached 0.802 with a sensitivity of 80.77%and a specificity of 68.25%.CONCLUSION Texture features extracted from DWI images and ADC maps are useful clues for predicting pathological T and N stages in rectal cancer.

Histogram analysis of apparent diffusion coefficient predicts response to radiofrequency ablation in hepatocellular carcinoma

Objective: The aim of this study was to predict tumor progression in patients with hepatocellular carcinoma(HCC) treated with radiofrequency ablation(RFA) using histogram analysis of apparent diffusion coefficients(ADC).Methods: Breath-hold diffusion weighted imaging(DWI) was performed in 64 patients(33 progressive and 31 stable) with biopsy-proven HCC prior to RFA. All patients had pre-treatment magnetic resonance imaging(MRI)and follow-up computed tomography(CT) or MRI. The ADC values(ADC_(10), ADC_(30_, ADC_(median) and ADC_(max))were obtained from the histogram's 10 th, 30 th, 50 th and 100 th percentiles. The ratios of ADC_(10), ADC_(30_,ADCmedian and ADCmax to the mean non-lesion area-ADC(RADC_(10), RADC_(30_, RADC_(median), and RADC_(max)) were calculated. The two patient groups were compared. Key predictive factors for survival were determined using the univariate and multivariate analysis of the Cox model. The Kaplan-Meier survival analysis was performed, and pairs of survival curves based on the key factors were compared using the log-rank test.Results: The ADC_(30_, ADCmedian, ADCmax, RADC_(30_, RADC_(median), and RADC_(max) were significantly larger in the progressive group than in the stable group(P<0.05). The median progression-free survival(PFS) was 22.9 months for all patients. The mean PFS for the stable and progressive groups were 47.7±1.3 and 9.8±1.3 months,respectively. Univariate analysis indicated that RADC_(10), RADC_(30_, and RADC_(median) were significantly correlated with the PFS [hazard ratio(HR)=31.02, 43.84, and 44.29, respectively, P<0.05 for all]. Multivariate analysis showed that RADCmedian was the only independent predictor of tumor progression(P=0.04). And the cutoff value of RADC_(median) was 0.71.Conclusions: Pre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA.

Apparent diffusion coefficient-based histogram analysis differentiates histological subtypes of periampullary adenocarcinoma

BACKGROUND For periampullary adenocarcinoma,the histological subtype is a better prognostic predictor than the site of tumor origin.Intestinal-type periampullary adenocarcinoma(IPAC)is reported to have a better prognosis than the pancreatobiliary-type periampullary adenocarcinoma(PPAC).However,the classification of histological subtypes is difficult to determine before surgery.Apparent diffusion coefficient(ADC)histogram analysis is a noninvasive,nonenhanced method with high reproducibility that could help differentiate the two subtypes.AIM To investigate whether volumetric ADC histogram analysis is helpful for distinguishing IPAC from PPAC.METHODS Between January 2015 and October 2018,476 consecutive patients who were suspected of having a periampullary tumor and underwent magnetic resonance imaging(MRI)were reviewed in this retrospective study.Only patients who underwent MRI at 3.0 T with different diffusion-weighted images(b-values=800 and 1000 s/mm^2)and who were confirmed with a periampullary adenocarcinoma were further analyzed.Then,the mean,5th,10th,25th,50th,75th,90th,and 95th percentiles of ADC values and ADCmin,ADCmax,kurtosis,skewness,and entropy were obtained from the volumetric histogram analysis.Comparisons were made by an independent Student's t-test or Mann-Whitney U test.Multiple-class receiver operating characteristic curve analysis was performed to determine and compare the diagnostic value of each significant parameter.RESULTS In total,40 patients with histopathologically confirmed IPAC(n=17)or PPAC(n=23)were enrolled.The mean,5th,25th,50th,75th,90th,and 95th percentiles and ADCmax derived from ADC1000 were significantly lower in the PPAC group than in the IPAC group(P<0.05).However,values derived from ADC800 showed no significant difference between the two groups.The 75th percentile of ADC1000 values achieved the highest area under the curve(AUC)for differentiating IPAC from PPAC(AUC=0.781;sensitivity,91%;specificity,59%;cut-off value,1.50×10^-3 mm^2/s).CONCLUSION Volumetric ADC histogram analysis at a b-value of 1000 s/mm2 might be helpful for differentiating the histological subtypes of periampullary adenocarcinoma before surgery.

Apparent diffusion coefficient in normal and abnormal pattern of intervertebral lumbar discs: initial experience

The aim of the present study was to compare the relationship of morphologically defined non-bulging/herni-ated, bulging and herniated intervertebral lumbar discs with quantitative apparent diffusion coefficient （ADC）. Thirty-two healthy volunteers and 28 patients with back pain or sciatica were examined by MRI. All intervertebral lumbar discs from L1 to S1 were classified according to morphological abnormality and degenerated grades. The ADC values of nucleus pulposus （NP） were measured and recorded. The significant differences about mean ADC values of NP were found between non-bulging/herniated discs and bulging discs as well as herniated discs （P 0.05）, whereas there were no significant differences in ADC values between bulging and herniated discs （P 0.05）. Moreover, statistically significant relationship was found in the mean ADC values of NP between ＂non-bulging/herniated and non-degenerated discs＂ and ＂non-bulging/herniated degenerated discs＂ as well as herniated discs （P 0.05）. Linear regression analysis between ADC value and disc level revealed an inverse correlation （r = -0.18）. The ADC map of the NP is a potentially useful tool for the quantitative assessment of componential and molecular alterations accompanied with lumbar disc abnormalities.

Combined value of apparent diffusion coefficient-standardized uptake value max in evaluation of post-treated locally advanced rectal cancer

AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive predictive value,in predicting the different group category response in related to TRG system,presented R^2 of 0.95.CONCLUSION:The functional imaging combining ADC and SUVmax in a single analysis permits to detect changes in cellular tissue structures useful for the assessment of tumour response after the neoadjuvant therapy in rectal cancer,increasing the sensitivity in correct depiction of treatment response than either method alone.

磁共振弥散成像的ADC直方图对子宫内膜癌分级分期及Ki⁃67表达的评估价值

目的:分析磁共振弥散表观弥散系数(ADC)直方图参数与子宫内膜癌的病理分级、分期及Ki⁃67表达的相关性,探讨ADC直方图的应用价值。方法:南通大学附属医院2016年1月至2022年10月的110例子宫内膜癌患者纳入研究,术前完成3 T磁共振弥散成像并由工作站获取ADC图,术后均有病理分级、分期以及Ki⁃67表达水平。Mann⁃Whitney U检验用于评估不同组之间ADC直方图参数的差异。通过Pearson相关分析评估Ki⁃67表达与ADC直方图参数之间的相关性。使用受试者工作特征(ROC)曲线分析评估不同组间差异参数的诊断性能。结果:(1)子宫内膜癌病理高、中、低分化组的ADCmean、ADCske和ADCkur分别为(1.37±0.53)×10^(-3)mm^(2)/s、1.36±0.52、1.70±0.64,(0.92±0.50)×10^(-3)mm^(2)/s、0.92±0.51、1.10±0.54,(0.73±0.40)×10^(-3)mm^(2)/s、0.73±0.41、0.86±0.41;国际妇产科联盟(FIGO)分期Ⅰ、Ⅱ、Ⅲ、Ⅳ期的ADCmean、ADCske、ADCkur分别为(1.38±0.53)×10^(-3)mm^(2)/s、0.11±0.69、0.38±1.79,(1.01±0.49)×10^(-3)mm^(2)/s、0.15±0.73、0.36±1.33,(0.74±0.40)×10^(-3)mm^(2)/s、0.06±0.47、0.59±0.55,(0.56±0.29)×10^(-3)mm^(2)/s、0.07±0.47、0.52±0.57。不同级及不同分期肿瘤之间的ADC直方图参数存在统计学差异。淋巴结阳性及阴性组的ADCmean、ADCske、ADCkur分别为(0.62±0.25)×10^(-3)mm^(2)/s、0.01±0.56、0.56±0.59,(1.14±0.55)×10^(-3)mm^(2)/s、0.03±0.72、0.28±1.46。淋巴结阳性组ADC参数显著低于淋巴结阴性组。(2)ADCmean、ADC10th、ADC50th、ADC90th和Ki⁃67表达之间存在显著的负相关。(3)在盆腔淋巴结阳性组与阴性组的ROC曲线分析中,ADCmean、ADC10th、ADC50th、ADC90th的曲线下面积(AUC)分别为0.816、0.776、0.803、0.834,ADC90th的AUC与ADC10th、ADC50th间有统计学差异。结论:ADC直方图定量参数有助于预测子宫内膜癌的分级、分期和淋巴结转移,也有助于肿瘤Ki⁃67表达的评估。

Apparent diffusion coefficient evaluation for secondary changes in the cerebellum of rats after middle cerebral artery occlusion

Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the cerebellum, which may be relevant to diaschisis. This phenomenon is often analyzed using positron emission tomography and single photon emission CT. However, these methods are expensive and radioactive. Thus, the present study quantified the changes of infarction core and remote regions after unilateral middle cerebral artery occlusion using apparent diffusion coefficient values. Diffu- sion-weighted imaging showed that the area of infarction core gradually increased to involve the cerebral cortex with increasing infarction time. Diffusion weighted imaging signals were initially in- creased and then stabilized by 24 hours. With increasing infarction time, the apparent diffusion co- efficient value in the infarction core and remote bilateral cerebellum both gradually decreased, and then slightly increased 3-24 hours after infarction. Apparent diffusion coefficient values at remote regions （cerebellum） varied along with the change of supratentorial infarction core, suggesting that the phenomenon of diaschisis existed at the remote regions. Thus, apparent diffusion coefficient values and diffusion weighted imaging can be used to detect early diaschisis.

DWI影像组学模型预测子宫内膜癌微卫星不稳定状态:与ADC值的对比研究

目的:探讨基于磁共振DWI的影像组学模型对子宫内膜癌(EC)微卫星不稳定(MSI)状态的预测价值。方法:回顾性分析2019年5月-2023年1月在本院确诊为EC的81例患者的DWI资料。其中,MSI组29例,微卫星稳定组(MSS)52例。在DWI图像上沿病变边缘逐层勾画ROI后生成容积ROI(VOI)并提取影像组学特征,并在生成的ADC图像上测量病灶的ADC值。采用最小绝对收缩和选择算子(LASSO)和SelectKBest算法进行组学特征的筛选,然后采用决策树(DT)分析方法构建组学预测模型。使用受试者工作特征(ROC)曲线评估模型的诊断效能,采用Delong检验比较影像组学模型与ADC之间诊断效能的差异。基于1000次采样的Bootstrap算法和校准曲线来验证预测模型的临床应用价值。结果:MSI组的ADC值小于MSS组(P=0.008)。模型构建方面,共筛选出5个最优DWI影像组学特征(2个一阶统计特征、1个直方图灰度共生矩阵特征、1个灰度共生矩阵特征和1个灰度游程长度矩阵特征)用于建立预测模型。诊断效能方面,DWI组学预测模型的AUC为0.927(95%CI:0.847~0.973),较ADC值的诊断效能(AUC=0.771,95%CI:0.664~0.857)显著增加(Z=2.436,P=0.015)。模型验证方面,在基于Bootstrap算法的验证中,DWI组学预测模型亦显示出较高的效能,AUC为0.904(95%CI:0.885~0.916);同时,校准曲线显示该模型的预测值与实际观测值之间有较好的一致性。结论:基于DWI影像组学特征构建的预测模型较ADC值能更好地对EC患者的MSI状态进行术前评估,有望为临床诊疗提供一种新的选择。

Whole lesion histogram analysis of apparent diffusion coefficient predicts therapy response in locally advanced rectal cancer

BACKGROUND Whole-tumor apparent diffusion coefficient(ADC)histogram analysis is relevant to predicting the neoadjuvant chemoradiation therapy(nCRT)response in patients with locally advanced rectal cancer(LARC).AIM To evaluate the performance of ADC histogram-derived parameters for predicting the outcomes of patients with LARC.METHODS This is a single-center,retrospective study,which included 48 patients with LARC.All patients underwent a pre-treatment magnetic resonance imaging(MRI)scan for primary tumor staging and a second restaging MRI for response evaluation.The sample was distributed as follows:18 responder patients(R)and 30 non-responders(non-R).Eight parameters derived from the whole-lesion histogram analysis(ADCmean,skewness,kurtosis,and ADC10^(th),25^(th),50^(th),75^(th),90^(th) percentiles),as well as the ADCmean from the hot spot region of interest(ROI),were calculated for each patient before and after treatment.Then all data were compared between R and non-R using the Mann-Whitney U test.Two measures of diagnostic accuracy were applied:the receiver operating characteristic curve and the diagnostic odds ratio(DOR).We also reported intra-and interobserver variability by calculating the intraclass correlation coefficient(ICC).RESULTS Post-nCRT kurtosis,as well as post-nCRT skewness,were significantly lower in R than in non-R(both P<0.001,respectively).We also found that,after treatment,R had a larger loss of both kurtosis and skewness than non-R(Δ%kurtosis and Δ skewness,P<0.001).Other parameters that demonstrated changes between groups were post-nCRT ADC10^(th),Δ%ADC10^(th),Δ%ADCmean,and ROIΔ%ADCmean.However,the best diagnostic performance was achieved byΔ%kurtosis at a threshold of 11.85%(Area under the receiver operating characteristic curve[AUC]=0.991,DOR=376),followed by post-nCRT kurtosis=0.78×10^(-3)mm^(2)/s(AUC=0.985,DOR=375.3),Δskewness=0.16(AUC=0.885,DOR=192.2)and post-nCRT skewness=1.59×10^(-3)mm^(2)/s(AUC=0.815,DOR=168.6).Finally,intraclass correlation coefficient analysis showed excellent intraobserver and interobserver agreement,ensuring the implementation of histogram analysis into routine clinical practice.CONCLUSION Whole-tumor ADC histogram parameters,particularly kurtosis and skewness,are relevant biomarkers for predicting the nCRT response in LARC.Both parameters appear to be more reliable than ADCmean from one-slice ROI.

Diffusion-weighted magnetic resonance imaging in cancer: Reported apparent diffusion coefficients,in-vitro and invivo reproducibility

There is considerable disparity in the published apparent diffusion coefficient(ADC) values across different anatomies. Institutions are increasingly assessing repeatability and reproducibility of the derived ADC to determine its variation,which could potentially be used as an indicator in determining tumour aggressiveness or assessing tumour response. In this manuscript,a review of selected articles published to date in healthy extracranial body diffusion-weighted magnetic resonance imaging is presented,detailing reported ADC values and discussing their variation across different studies. In total 115 studies were selected including 28 for liver parenchyma,15 for kidney(renal parenchyma),14 for spleen,13 for pancreatic body,6 for gallbladder,13 for prostate,13 for uterus(endometrium,myometrium,cervix) and 13 for fibroglandular breast tissue. Median ADC values in selected studies were found to be 1.28 × 10-3 mm2/s in liver,1.94 × 10-3 mm2/s in kidney,1.60 × 10-3 mm2/s in pancreatic body,0.85 × 10-3 mm2/s in spleen,2.73 × 10-3 mm2/s in gallbladder,1.64 × 10-3 mm2/s and 1.31 × 10-3 mm2/s in prostate peripheral zone and central gland respectively(combined median value of 1.54×10-3 mm2/s),1.44 × 10-3 mm2/s in endometrium,1.53 × 10-3 mm2/s in myometrium,1.71 × 10-3 mm2/s in cervix and 1.92 × 10-3 mm2/s in breast. In addition,six phantom studies and thirteen in vivo studies were summarized to compare repeatability and reproducibility of the measured ADC. All selected phantom studies demonstrated lower intra-scanner and inter-scanner variation compared to in vivo studies. Based on the findings of this manuscript,it is recommended that protocols need to be optimised for the body part studied and that system-induced variability must be established using a standardized phantom in any clinical study. Reproducibility of the measured ADC must also be assessed in a volunteer population,as variations are far more significant in vivo compared with phantom studies.

DWI检查的ADC值与胰腺癌伴肝转移患者治疗预后的关系

目的探讨弥散加权成像(DWI)检查的表观扩散系数(ADC)值与胰腺癌伴肝转移患者治疗预后的关系。方法回顾性分析2019-10至2022-01于海军安庆医院收治的经病理学检验确诊为胰腺癌伴肝转移的96例患者,行常规MRI联合增强扫描。收集患者的相关资料,分析患者DWI的ADC值的水平,对患者进行随访,以术后12个月为随访止点,根据患者的存活情况,将患者分为存活组(n=63)和死亡组(n=33),采用多因素Logistic回归分析影响患者治疗预后的独立影响因素。结果单因素分析结果显示,两组患者的年龄、胰肿瘤最大直径、肝转移瘤直径、肝转移瘤数目、淋巴结转移情况、肿瘤分化程度、Alb、ADC值均存在统计学差异(P<0.05),而两组患者的性别、BMI、肿瘤位置、神经侵犯情况、Hb、PLT差异并无统计学意义(P>0.05)。多因素分析结果显示,肝转移瘤数目[OR=2.702,95%CI(1.340,5.450)]、血管侵犯[OR=1.906,95%CI(1.052,3.452)]、肿瘤分化程度[OR=1.269,95%CI(1.025,1.571)]、ADC值[OR=0.422,95%CI(0.216,0.824)]均为影响胰腺癌伴肝转移患者治疗预后的独立影响因素(P<0.05),其中ADC值为独立保护性因素,其余皆为独立危险因素。结论肝转移瘤数目、淋巴结转移、肿瘤分化程度、ADC值均为影响胰腺癌伴肝转移患者治疗预后的独立影响因素,临床可根据相应情况进行治疗方案的调整与完善。

乳腺良恶性肿瘤钆喷酸葡胺增强后不同时间点ADC值的评估

目的探讨钆喷酸葡胺增强对乳腺病变表观扩散系数(ADC)值的影响,以及增强前及增强后3 min、13 min的ADC值在乳腺良恶性肿瘤中的鉴别效能。方法回顾性分析本院经病理证实的272个乳腺病灶增强前后肿瘤实质的ADC值,分别比较浸润性乳腺癌组、非浸润性乳腺癌组及良性肿瘤组间在增强后3 min、13 min与增强前的ADC值的差异,并绘制ROC曲线,分析其诊断效能。结果浸润性乳腺癌组增强前及增强后3 min的ADC值分别为(0.999±0.167)×10^(-3) mm^(2)/s、(0.934±0.165)×10^(-3) mm^(2)/s,差异有统计学意义(P<0.001),余病理类型增强前后ADC值差异均无统计学意义。增强前、增强后3 min区分肿瘤良恶性ADC值截断值分别为1.23×10^(-3)、1.31×10^(-3) mm^(2)/s,敏感度为92.3%、80.8%,特异度为96.3%、100%;增强前、增强后13 min区分肿瘤良恶性ADC值截断值分别为1.22×10^(-3)、1.30×10^(-3) mm^(2)/s,敏感度为95.7%、92.4%,特异度为91.3%、95.0%;增强前及增强后3 min、13 min的ADC值诊断乳腺病变良恶性的AUC均大于0.95。结论浸润性乳腺癌组增强后3 min ADC值有所下降,但不影响乳腺良恶性肿瘤的鉴别效能;在增强后3 min采集扩散加权成像序列有助于减少总检查时间。

联合ADC组学标签和激素受体预测乳腺癌新辅助化疗病理完全化解

目的探讨使用联合ADC图组学标签和激素受体模型来预测乳腺癌新辅助化疗(NC)病理完全缓解的价值。方法共收集了165例NC前行DWI检查女性乳腺癌患者资料,年龄在28-70岁之间。基于ADC共提取了396个组学特征并进行特征筛选。比较病理完全缓解和病理部分缓解组间临床特征的差异。将有差异临床特征和最优影像组学特征纳入logistic回归以建立模型。使用ROC曲线和决策曲线来评估模型的效能。结果在训练集和测试集中,激素受体表达状态在病理完全缓解和病理部分缓解组间的差异均具有统计学意义(P<0.05)。基于ADC图组学标签模型在训练集和测试集中预测乳腺癌NC病理完全缓解的曲线下面积(AUC)分别为0.785和0.639。基于联合ADC图组学标签和激素受体建立的联合模型在训练集和测试集中预测乳腺癌NC病理完全缓解的AUC分别为0.904和0.789。联合模型的临床获益高于基于ADC图组学标签模型。结论联合ADC图学标签和激素受体建立的联合模型对预测乳腺癌NC病理完全缓解具有较好的价值。

Correlation of magnetic resonance imaging quantitative parameters and apparent diffusion coefficient value with pathological breast cancer

BACKGROUND China ranks 120th worldwide for the incidence of breast cancer and 163rd for mortality.Early screening,diagnosis,and timely determination of the optimal treatment plan can help ensure clinical efficacy and prognosis.AIM To investigate the relationship between quantitative magnetic resonance imaging parameters,apparent diffusion coefficient value,pathological immunohistochemical status,and patient prognosis.METHODS A total of 108 patients with breast cancer(breast cancer group)and 110 patients with benign breast tumors(benign group)confirmed by pathological examination at our Hospital from September 2013 to August 2016 were selected.All patients had undergone preoperative magnetic resonance imaging(MRI)examinations,and the quantitative parameters of MRI and apparent diffusion coefficient(ADC)values for the two groups were compared.The MRI quantitative parameters and ADC values of patients with different estrogen receptor(ER),progesterone receptor,and human epidermal growth factor receptor-2 expression were statistically analyzed.The relationship between the quantitative parameters of MRI and ADC values and patient recurrence was analyzed using receiver operating curves.RESULTS The measured values of the quantitative parameters of MRI-Ktrans,Kep,and Ve in the breast cancer group were higher than those in the benign group;the ADC value in the breast cancer group was lower than that in the benign group,and the difference was statistically significant(P<0.05).The Ktrans,Ve,and ADC values in patients with ER-positive breast cancer were significantly lower than those in patients with negative ER expression(P<0.05).After 5 years of follow-up,22 patients with breast cancer experienced postoperative recurrence.The Kep,Ve,and ADC values of the recurrence group were significantly lower than those of the non-recurrence group,and the difference was statistically significant(P<0.05).CONCLUSION MRI quantitative parameters and ADC are related to the expression of breast cancer-related immunological receptor factors and have certain clinical value in assessing postoperative recurrence in patients.

基于VI-RADS和ADC直方图分析术前预测膀胱癌肌层浸润的价值

目的本研究旨在探讨膀胱影像报告和数据系统(VI-RADS)和体积表观扩散系数(ADC)直方图参数评估膀胱癌肌层浸润的价值,并探讨两者的相关性。方法回顾性分析81例经尿道膀胱肿瘤电切术或根治性膀胱切除术病理证实的膀胱癌患者,由两名放射科医生运用VI-RADS评分方法对病灶进行标准化评分。从ADC图中获得每个病变的体积ADC直方图参数,比较VI-RADS及量化参数在肌层浸润性膀胱癌(MIBC)和非肌层浸润性膀胱癌(NMIBC)间的差异,对有意义的参数绘制受试者工作特征曲线评估各模型的预测能力。结果最终纳入40例(49.4%)肌层浸润性膀胱癌,41例(50.6%)非肌层浸润性膀胱癌,53个(65.4%)病灶VI-RADS大于等于3分,28个(34.6%)病灶VI-RADS小于3分。在所有参数中,VI-RADS的曲线下面积(AUC)值最高(AUC=0.903)。ADC_(min)、ADC_(media)、ADC_(mean)、10%ADC(第10百分位数ADC值)、25%ADC(第25百分位数ADC值)、75%ADC(第75百分位数ADC值)、90%ADC(第90百分位数ADC值)的数值MIBC组低于NMIBC组,且与VI-RADS评分呈负相关(r=-0.439、-0.526、-0.305、-0.368、-0.547、-0.527、-0.396,P均<0.05);峰度、熵MIBC组高于NMIBC组,与VI-RADS评分呈正相关(r=0.593、0.296,P均<0.05)。VI-RADS+75%ADC、VI-RADS+ADC_(media)、VI-RADS+ADC_(mean)与单独使用VI-RADS相比有统计学差异(P值分别为0.038、0.018、0.029),其中结合ADC_(media)的VI-RADS获得了最大的AUC值(AUC=0.950)。结论VI-RADS和体积ADC直方图分析可有助于判定膀胱癌是否肌层浸润,同时两者存在一定相关性,体积ADC直方图可以为VI-RADS提供进一步的信息补充。

The apparent diffusion coefficient does not reflect cytotoxic edema on the uninjured side after traumatic brain injury

After traumatic brain injury, vasogenic and cytotoxic edema appear sequentially on the involved side. Neuroimaging investigations of edema on the injured side have employed apparent diffusion coefficient measurements in diffusion tensor imaging. We investigated the changes occurring on the injured and uninjured sides using diffusion tensor imaging/apparent diffusion coefficient and histological samples in rats. We found that, on the injured side, that vasogenic edema appeared at 1 hour and intracellular edema appeared at 3 hours. Mixed edema was observed at 6 hours, worsening until 12–24 hours post-injury. Simultaneously, microglial cells proliferated at the trauma site. Apparent diffusion coefficient values increased at 1 hour, decreased at 6 hours, and increased at 12 hours. The uninjured side showed no significant pathological change at 1 hour after injury. Cytotoxic edema appeared at 3 hours, and vasogenic edema was visible at 6 hours. Cytotoxic edema persisted, but vasogenic edema tended to decrease after 12–24 hours. Despite this complex edema pattern on the uninjured side with associated pathologic changes, no significant change in apparent diffusion coefficient values was detected over the first 24 hours. Apparent diffusion coefficient values accurately detected the changes on the injured side, but did not detect the changes on the uninjured side, giving a false-negative result.