UNASSIGNED: A total of 108 paired DWI and DCE-MRI scans were acquired at 1.5 T from 40 patients with primary breast cancer (median age: 44.5 years) before and during neoadjuvant chemotherapy (NACT). DWI parameters included apparent diffusion coefficient (ADC), tissue diffusion (Dt), pseudo-diffusion coefficient (Dp), perfused fraction (f), and the product f×Dp (microvascular blood flow). DCE-MRI parameters included blood flow (Fb), blood volume fraction (vb), interstitial volume fraction (ve) and extracellular volume fraction (vd). All were extracted from three tumor regions of interest (whole-tumor, ADC cold-spot, and DCE-MRI hot-spot) at three MRI visits: pre-treatment, after one, and three cycles of NACT. Spearman\'s rank correlation was used for assessing between-subject correlations (r), while repeated measures correlation was employed to assess within-subject correlations (rrm) across visits between DWI and DCE-MRI parameters in each region.
UNASSIGNED: No statistically significant between-subject or within-subject correlation was found between the perfusion parameters estimated by IVIM and DCE-MRI (f versus vb and f×Dp versus Fb; P=0.07-0.81). Significant moderate positive between-subject and within-subject correlations were observed between ADC and ve (r=0.461, rrm=0.597) and between Dt and ve (r=0.405, rrm=0.514) as well as moderate positive within-subject correlations between ADC and vd and between Dt and vd (rrm=0.619 and 0.564, respectively) in the whole-tumor region.
UNASSIGNED: No correlations were observed between the perfusion parameters estimated by IVIM and DCE-MRI. This may be attributed to imprecise estimates of fxDp and vb, or an underlying difference in what IVIM and DCE-MRI measure. Care should be taken when interpreting the IVIM parameters (f and f×Dp) as surrogates for those measured using DCE-MRI. However, the moderate positive correlations found between ADC and Dt and the DCE-MRI parameters ve and vd confirms the expectation that as the interstitial and extracellular volume fractions increase, water diffusion increases.
■在新辅助化疗(NACT)之前和期间,在1.5T时从40例原发性乳腺癌患者(中位年龄:44.5岁)中获得了108个成对的DWI和DCE-MRI扫描。DWI参数包括表观扩散系数(ADC),组织扩散(Dt),伪扩散系数(Dp),灌注分数(f),和乘积f×Dp(微血管血流量)。DCE-MRI参数包括血流量(Fb),血液体积分数(vb),间质体积分数(ve)和细胞外体积分数(vd)。全部从三个感兴趣的肿瘤区域(整个肿瘤,ADC冷点,和DCE-MRI热点)在三次MRI访问中:治疗前,在一个之后,和三个周期的NACT。Spearman的等级相关性用于评估受试者之间的相关性(r),而重复测量相关性用于评估每个区域的DWI和DCE-MRI参数之间的受试者内相关性(rrm)。
■在通过IVIM和DCE-MRI估计的灌注参数之间没有发现统计学上显著的受试者之间或受试者内相关性(f对vb和f×Dp对Fb;P=0.07-0.81)。在ADC与ve(r=0.461,rrm=0.597)和Dt与ve(r=0.405,rrm=0.514)之间观察到受试者之间和受试者内的显着中度正相关,以及整个肿瘤区域中ADC与vd之间以及Dt与vd之间的中度正相关(rrm分别为0.619和0.564)。
■通过IVIM和DCE-MRI估计的灌注参数之间没有观察到相关性。这可能归因于fxDp和vb的不精确估计,或者IVIM和DCE-MRI测量的潜在差异。在将IVIM参数(f和f×Dp)解释为使用DCE-MRI测量的参数时,应格外小心。然而,ADC和Dt与DCE-MRI参数ve和vd之间的中度正相关证实了随着间质和细胞外体积分数的增加,水扩散增加。