Dynamic Resonance Imaging Research Articles

IBC-Oxford University2023_BJSOral_1Dynamic Magnetic Resonance Imaging (Dy-MRI) Evaluation of the Impact of Endoscopic Sleeve Gastroplasty (ESG) on Gastric Structure and Function in Morbid Obese Patients

Abstract Introduction Endoscopic sleeve gastroplasty (ESG) is a restrictive endoluminal bariatric procedure consisting in the application of multiple full-thickness sutures to reduce gastric capacity (GC) and slow down gastric emptying (GE). Although results are promising, a large variation in the weight loss outcomes is reported. Dynamic resonance imaging (Dy-MRI) has been successfully applied for the assessment and analysis of gastrointestinal (GI) function. It permits to acquire large field-of-view, dynamic, high- resolution, three-dimensional (3D) image data with excellent soft-tissue contrast in less than a second3. In addition, our group previously demonstrated a significant correlation between weight loss and gastric anatomy changes assessed by Dy-MRI in laparoscopic sleeve gastrectomy (LSG) patients. The aim of this study is to use Dy-MRI to objectively assess gastric structural and functional changes 6 months after ESG and their impact on weight loss. Material and methods Prospective single centre study. Patients underwent preoperative and postoperative (after 6 months) Dy-MRI to evaluate total GC and GE changes, immediately after the ingestion of 400 ml of liquid meal and over time up to 120 minutes after ingestion (T120). Only patients with a complete follow up at and 6 months (M6) were included. Demographic data, pre- and intra-operative data, and weight loss outcomes were collected. Continuous variables were reported as median and interquartile rank (IQR), while categorical variables as numbers and percentages. Results From July 2021 to June 2023, 16 ESG patients participated in this study. Patients had a median age of 41.5 years (IQR:35-49.7) with a median BMI (kg/m2) of 36.9 (IQR: 34.08-42.18). A median number of 6 (IQR: 5.2-6) purse string sutures were placed during the ESG. There were no complications. At the follow-up gastroscopy at M6 all patients presented an intact ESG with all the suture still present. Dy- MRI showed a median GC reduction of 34.1% of the initial volume (p<0.0001) and GE decreased by 0.43 mL/min (p=0.01). As a whole, the study population had a 16.8% of total weight loss (TWL) at M6 (p<0.0001). Similarly, the median BMI decreased from 36.9 to 29.9 (p=0.01). %TWL varied from 15.5 at M3 to 18.3 at M6. During the same time-elapse, %EWL increased from 46.4 to 57.1. Discussion and Conclusion Dy- MRI is confirmed to be a non-invasive method capable of objectively quantify gastric volume reduction and GE changes after ESG. It is likely that these two factors play a synergic role in the weight loss journey of patients undergoing ESG. Further investigations in a larger sample are needed to support these initial findings and to support an evidence based, patient specific approach to endoscopic gastric remodelling.

Correlation analysis between short-term invasive recurrence and functional MRI after radiofrequency ablation of hepatocellular carcinoma

Objective To explore and clarify the correlation between short-term aggressive intrasegmental recurrence (AIR) and functional magnetic resonance imaging after radiofrequency ablation of hepatocellular carcinoma (HCC). Methods A retrospective analysis of 1 262 patients with HCC who underwent radiofrequency ablation (RFA) in our hospital from January 2012 to June 2018, all patients were confirmed by pathology as HCC, of which 30 patients were found to have AIR during radiographic follow-up within 3 months after surgery, another 35 patients with disease progression who were controlled in a short period of time were randomly selected as the control group. All the enrolled patients underwent dynamic enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) scanning before surgery, and the differences in clinical data, lesion location, and functional magnetic resonance parameters between the two groups were compared, and their correlation with AIR after RFA was analyzed. Chi-square test, t test and Pearson test were used. Results The lesions in the AIR group were significantly more in the Ⅰand Ⅳsegments than that in the control group (P 0.05). There was no significant difference in the lesion morphology between the two groups (P>0.05), and there was a significant difference in the early enhancement pattern of the lesions (P<0.05), and the early arterial enhancement rate and apparent diffusion coefficient (ADC) value of the AIR group were significantly lower than the control group (P<0.05). Further correlation analysis found that early enhancement of the arterial artery, early arterial enhancement rate, ADC value and lesion location were associated with AIR and were positively correlated, r values were 0.455, 0.633, 0.518, 0.375 and 0.287 (P<0.05). Conclusion The short-term AIR and functional imaging parameters (arterial early enhancement, early arterial enhancement rate, ADC value) and the liver segment (Ⅰ and Ⅳ) were highly correlated with radiofrequency ablation. Key words: Liver neoplasms; Radiofrequency ablation; Aggressive intrasegmental recurrence; Magnetic resonance imaging

The clinical value of DCE-MRI Semi-quantitative parameters in monitoring neoadjuvant chemotherapy response of osteosarcoma

Objective To evaluate the response of neoadjuvant chemotherapy on osteosarcoma by semi-quantitative parameters of dynamic contrast-enhancement magnetic resonance imaging (DCE-MRI). Methods Retrospectively analysis 25 cases of osteosarcoma confirmed by pathology.All cases received DCE-MRI scan before and after 4 cycles of neoadjuvant chemotherapy.The following semi-quantitative parameters were calculated by post-processing software: early dynamic enhancement wash-in slope (Slope), maximum signal intensity (SImax), time to peak (TTP), signal enhanced extent (SEE), peak percent enhancement (PPE), wash out rate (WOR), enhancement rate (R). All cases were divided into good response group (tumor necrosis rate ≥90%, n=12) and non-response group (tumor necrosis rate <90%, n=13) according to the Huvos grading method. Semi-quantitative parameters of DCE-MRI before and after neoadjuvant chemotherapy between good response group and non-response group were compared by Mann-whitney U test. Receiver operating characteristic curve (ROC) analysis was performed to evaluate the efficacy of different good response group and non-response group after neoadjuvant chemotherapy (NAC). Results Slope, SImax, TTP, SEE, PPE, WOR, R, TTP, WOR before and after NAC in good response group were significant different (P<0. 05), but only SImax, SEE in non-response group. TTP, R were significant different between the above two groups before NAC, and Slope, SImax, TTP, SEE, WOR, R were significant different after NAC (P<0.05). ROC was used to predict the diagnostic efficiency of various parameters for tumor necrosis rate after osteosarcoma NAC. It was found that the sensitivity and specificity of Slope, TTP and R parameters for predicting the response of osteosarcoma after chemotherapy were 83.3% and 92.3%, 91.7% and 69.2%, 84.6% and 75.0% respectively. The area under the curve (AUC) were 0.872 (95% CI: 0.716 to 1.027), 0.846 (95% CI: 0.685 to 1.007), 0.833 (95% CI: 0.662 to 1.004), the cut-off value were 0.032, 175 s, 5.441, Youden index were 0.756, 0.609, 0.596, respectively. Conclusions Slope, TTP, R were the most valuable semi-quantitative parameter of DCE-MRI to predict the response of NAC in osteosarcoma. Key words: Osteosarcoma; Neovascularization, pathologic; Magnetic resonance imaging; Magnetic resonance angiography

Application value of dynamic contrast-enhanced magnetic resonance imaging and conventional magnetic resonance imaging in evaluation of hepatocellular carcinoma before and after TACE treatment

Objective To compare the application of dynamic contrast-enhanced magnetic resonance imaging (MRI) and conventional MRI in the detection of hepatocellular carcinoma (HCC) lesions before and after transcatheter arterial chemoembolization (TACE) treatment and evaluation of the effect of TACE treatment, thus to judge its application value, and to provide guidance for early clinical diagnosis. Methods Seventy-six patients with HCC who underwent TACE in Pingyang Hospital Affiliated to Wenzhou Medical University from January 2018 to December 2018 were selected in the research.According to the random number table method, 76 patients were randomly divided into control group and study group, with 38 cases in each group.The control group was examined by conventional MRI, while the study group was examined by dynamic enhancement of MRI.The lesions were observed before and after treatment, and Ktrans, Kep and ve of the two groups were recorded before and after treatment.The accuracy, sensitivity and specificity of the two groups were compared. Results Before and after treatment, the total detection rates of the study group (92.05%, 100.00%) were significantly higher than those of the control group (80.85%, 71.43%) (χ2=16.489, 15.246, all P 0.05). After treatment, the Ktrans and Kep values of the two groups were significantly decreased, and the Ktrans[(0.419±0.101)min] and Kep[(1.073±0.237)min] values of the study group were significantly lower than those of the control group [(0.647±0.128)min, (1.158±0.221)min], the differences were statistically significant (t=9.485, 5.642, all P>0.05). There was no statistically significant difference in ve value between the two groups (t=1.025, P>0.05). The accuracy and sensitivity of detection in the study group (92.11%, 97.37%) were significantly higher than those in the control group (81.58%, 84.21%), and the specificity (94.74%) of the study group was significantly lower than that of the control group (97.37%) (χ2=17.186, 14.453, 6.489, all P<0.05). Conclusion Dynamic contrast-enhanced MRI is more effective in the detection of HCC patients before and after TACE treatment.It is convenient to provide guidance for treatment and has higher clinical application value.It is worthy of popularizing. Key words: Liver neoplasms; Chemoembolization, therapeutic; Magnetic resonance imaging; Dynamic enhancement; Conventional magnetic resonance; Quantitative parameters; Curative effect; Application value

Correlation of quantitative parameters of dynamic enhanced magnetic resonance imaging with Dukes stage, lymph node metastasis and tumor differentiation degree of rectal cancer

Objective To explore the correlation between quantitative parameters of dynamic enhanced magnetic resonance imaging (DCE-MRI) and Dukes stage, lymph node metastasis, tumor differentiation degree and molecular biological indicators [Ki67 and human epidermal growth factor receptor 2 (CerbB-2)] of rectal cancer. Methods This study was a prospective study. From October 2014 to October 2017, 168 cases of rectal cancer patients were selected as the research objects. DCE-MRI was performed preoperatively to obtain the quantitative parameter values of region of interest (ROI) [apparent diffusion coefficient (ADC)mean, Ktrans, Ve, and Kep] in tumor site. The expression of Ki67 and CerbB-2 were detected by immunohistochemical. Correlations of DCE-MRI quantitative parameter values and rectal cancer Dukes staging, lymph node metastasis, tumor differentiation degree to Ki67 and CerbB-2 expression level were analysised. Results With the increase of tumor differentiation, ADCmean was increasing, while Ktrans and Ve showed a downward trend, with significant difference (P 0.05). The ADCmean was statistically significant between different groups (P 0.05). The ADCmean of lymph node metastasis group was significantly lower than that of no lymph node metastasis group (P<0.001), while Ktrans, Ve and Kep were significantly higher than that of no lymph node metastasis group (P<0.001). With the increase of Dukes staging in rectal cancer, ADCmean was decreasing and Ktrans was increasing, with statistically significant difference (P<0.001); among which the ADCmean of Dukes A and B was significantly higher than that of Dukes C and D (P<0.05), and Ktrans was significantly lower than that of Dukes C and D (P<0.05). Ktrans and Kep were increased with the increased expression levels of Ki67 and CerbB-2, and the difference between Ktrans and Kep was statistically significant (P<0.05). The ADCmean decreased with the increase of Ki67 and CerbB-2 expression level, and the difference was statistically significant (P<0.05). Conclusions DCE-MRI quantitatively participates can reflect the biological behavior of rectal cancer, and can be used to evaluate the prognosis of tumors and guide the clinical selection of more appropriate treatment options. Key words: Rectal neoplasms; Magnetic resonance imaging; Diagnosis, computer-assisted; Ki-67 antigen; Receptor, erbB-2

Diagnostic value of multiparametric-MRI in T staging of bladder cancer

Objective To evaluate the clinical significance of multiparametric-MRI(mpMRI) in the prediction of T stage in bladder cancer and predicting muscle invasive bladder carcinomas. Methods From March 2015 to March 2017, 75 patients with bladder cancer were retrospectively reviewed with high-resolution T2-weighted images (HR-T2WI), diffusion weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and other the clinical data such as ADC of muscular layer in normal and carcinomas bladder. The accuracy of these techniques was used to diagnose the T stage, and the ROC curve was used to analyze the ability of ADC to diagnose muscle invasive bladder carcinomas. Results The accuracy of the mpMRI (88.00%)was superior to DWI (76.00%), DCE-MRI (66.67%) and HR-T2WI (66.67%) in differentiating non-muscle invasive from muscle invasive. The agreement between the mpMRI and histopathological staging (kappa=0.816) were also best. The ROC curve of muscle invasive bladder carcinomas was 0.983 (P=0.01). Conclusions The mpMRI is an effective tool for determining local T stages and muscle invasive bladder carcinomas. Key words: Urinary Bladder Neoplasms; Magnetic Resonance Spectroscopy

Histogram analysis of dynamic contrast enhancement MRI in predicting long-term treatment effect of cervical cancer after chemoradiotherapy

Objective To investigate the potential value of pre-treatment dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in predicting long-term survival of cervical cancer treated by concurrent chemoradiotherapy. Methods Uterine cervical cancer patients who received chemo-radiation therapy during 2008 to 2014 in a single institute were retrospectively collected and followed up. Pre-treatment DCE-MRI images were retrieved to generate four hemodynamic related parameters including positive enhancement integral (PEI), maximum slop of increase (MSI), maximum slope of decrease (MSD) and signal enhancement ratio (SER). Region of interests were drawn manually on T2WI along the rim of tumors on each slice, and were then registered to DCE-MRI parametric maps. Histogram analysis software was used to calculate the mean, median, maximum, minimum,10th percentile, 90th percentile, kurtosis and skewness values for each DCE-MRI parameters. Median follow-up time was 54.7 months (range 2.1 to 94.6 months).Uni-and multivariable Cox regression analyses were used to evaluate correlation between the above values and the disease free survival (DFS). Kaplan-Meier curve was used to evaluate survival time. Results Of the 75 patients, 16 of them died from cervical cancer, 3 patients had metastasis, and 1 patient continued to progress. Median, mean, 10th and 90th percentile from MSI, and minimum, kurtosis, skewness were the influencing factors of disease-free survival of cervical cancer with concurrent chemoradiotherapy(P<0.1) Pearson relationship analysis and multivariable Cox regression analysis was performed which indicated PEI kurtosis value of cervical cancer was an independent influencing factor for cervical cancer without disease survival (hazard ratio 1.658, P=0.001). Conclusion PEI kurtosis was an independent factor for DFS of locally advanced cervical cancer treated with concurrent chemoradiotherapy. Key words: Uterine cervical neoplasms; Long-time survival; Magnetic resonance imaging; Histogram analysis

Application of quantitative imaging technique in the diagnosis of pancreatic cancer

Pancreatic cancer is a malignant tumor, and the clinical manifestations are not characteristic, so it is difficult to diagnose at an early stage, and it has a poor prognosis.Image technology has been widely used in clinical, with mature technology, and the application of image technology not only confined to the image display, but also has become a hot spot of research, including dynamic contrast enhancement magnetic resonance imaging (DCE-MRI), intravoxel incoherent motion (IVIM), CT perfusion imaging, which could analyze quantitatively the permeability and microvascular of lesions, to improve the sensitivity of diagnosis, and to assess quantitatively the effect of drugs, radiation and chemotherapy. Key words: Pancreatic neoplasms; Radiographic image interpretation, computer-assisted; Magnetic resonance imaging; Intravoxel Incoherent Motion (IVIM); Perfusion imaging; Review

Clinical significance of 3.0T dynamic contrast-enhanced nuclear magnetic resonance imaging in elderly patients with prostate cancer

Objective To explore clinical diagnosis significance of 3.0T dynamic contrast-enhanced nuclear magnetic resonance imaging(DCE-MRI) in elderly patients with prostate cancer(PC). Methods This study contained 45 patients, including 30 cases of PC and 15 cases of benign prostatic hyperplasia, diagnosed and treated in our hospital from January 2016 to January 2017. All patients underwent magnetic resonance imaging (MRI) and DCE-MRI examinations, whose results were compared with the pathological results. The volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular volume fraction (Ve) values of central gland non cancer area, peripheral non cancer area, prostate cancer area were measured, PC group were divided further according to the Gleason score ≤ 7 points, 8 points, 9 points, 10 points. Results The Ktrans, Kep and Ve values of central gland non cancer area were significantly different from those in peripheral non cancer area and prostate cancer area (P 0.05). Ktrans and Gleason scores had positive correlation in prostate cancer area (r=0.654, P<0.05). Conclusions 3.0T DCE-MRI provides an objective basis for diagnosis of elderly patients with prostate cancer. Key words: Prostatic Neoplasms; Magnetic Resonance Imaging; Aged

Application value of different model of dynamic contrast-enhanced magnetic resonance imaging in pathological grading of breast invasive ductal carcinoma

Objective To explore the application value of different dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) models in pathological grading of breast invasive ductal carcinoma. Methods Forty-five cases of breast invasive ductal carcinoma confirmed by clinical pathology from June 2016 to October 2017 in Shanxi Provincial People's Hospital were enrolled in this study. Grade 1 and 2 invasive ductal carcinomas were classified into the low-grade group, grade 3 invasive ductal carcinomas was classified as the high-grade group. The whole patients underwent DCE-MRI scans. Volume transport constant (Ktrans) was obtained by using the Extended Tofts Linear model with population arterial input function (AIF). Then, the Reference Region model was used to obtain the reference region model volume transport constant (RRKtrans). The performances of histogram analysis of these two quantitative parameters in pathological grading of breast invasive ductal carcinoma were compared. Results The mean, 25 %, 50 %, 75 %, 90 % percentiles, kurtosis and skewness of RRKtransin in high grade group were (0.793±0.258)/min, (0.484±0.209)/min, (0.773± 0.277)/min, (1.066±0.351)/min, (1.322±0.406)/min, 2.647 (1.426, 3.679), 0.398 (0.297, 0.514) respectively, and the corresponding parameters in low grade group were (0.506±0.203)/min, (0.301±0.142)/min, (0.487±0.211)/min, (0.692±0.281)/min, (0.861±0.323)/min, 1.725 (0.779, 2.316), 0.258 (0.133, 0.302) respectively. There were significant differences between the two groups (all P < 0.05). The mean, 50 %, 75 %, 90 % percentiles of Ktrans in high grade groups were (0.099±0.034)/min, (0.110±0.033)/min, (0.132±0.045)/min, (0.140±0.047)/min respectively, and the corresponding parameters in low grade group were (0.067±0.030)/min, (0.082±0.067)/min, (0.096±0.059)/min, (0.113±0.074)/min respectively. There were significant differences between the two groups (all P < 0.05). RRKtrans was superior to Ktrans in distinguishing area under the curve (AUC) of receiver operating characteristic curve (ROC) of high and low grading of breast invasive ductal carcinoma. Conclusion RRKtrans obtained by Reference Region model and Ktrans obtained by Population AIF DCE-MRI have some values in pathological grading of breast invasive ductal carcinoma, but the performance of RRKtrans is superior to Ktrans. Key words: Breast neoplasms; Dynamic contrast-enhanced magnetic resonance imaging; Reference region model; Arterial input function

Current application and prospect of dynamic contrast enhanced magnetic resonance imaging in the diagnosis and treatment of tumors

Tumor angiogenesis is closely related to the biological behavior of tumor tissue. Microvessel density is the gold standard to evaluate tumor angiogenesis, but it is invasive. Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), a robust imaging method, is commonly used to non-invasively characterize changes in tumor vascularity and to assess the therapeutic effect of anticancer strategies. This review introduces the DCE-MRI and its current application in the diagnosis and treatment of tumor. Key words: Neoplasms; Diagnosis; Treatment outcome; Magnetic resonance imaging; Trends

Apparent diffusion coefficient map based radiomics model in differentiating benign from malignant entity in breast imaging-reporting and data system 4 breast lesions

Objective To investigate the diagnostic values of radiomics model based on ADC map in differentiating benign from malignant lesions in suspicious breast findings with MRI breast imaging reporting and data system (BI-RADS) category 4. Methods Eighty eight patients (36 benign and 52 malignant) with diagnosis of MRI BI-RADS 4 in our hospital from December 2014 to December 2015 were retrospectively enrolled in this study. All the patients were proved by pathology and examined by sequence of T1WI, T2WI, DWI and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI), and then were further sub-categorized into BI-RADS 4A, BI-RADS 4B, or BI-RADS 4C based on DCE-MRI sequence. Thus positive predictive value (PPV) of each sub-category were calculated and ROC were used to describe its efficiency in differential diagnosis. Radiomics features based on ADC map were generated automatically from Analysis-Kinetics (GE Healthcare). Sixty three of the 88 cases randomized-selected by computer were used to establish forecasting models and other 25 cases for validation. Kruskal-Wallis test and Spearman were introduced to reduce radiomics features that were highly correlated with others. Logistic linear regression (LLR) model was constructed based on the selected features by 'glm’ function in R software and then verified by 10-fold cross validation (repeat 10 times). ROC was curved to determine the diagnostic accuracy of the model. Results The PPV of BI-RADS 4A,4B,4C were 16.7% (2/12) ,59.6% (28/47) ,75.9% (22/29) respectively. Area under curve (AUC) of ROC was 0.650, sensitivity and specificity were 76.9% and 45.9% respectively. Three hundred and ninety six radiomics features were extracted automatically by software and 5 features (size zone variability, difference entropy, zone percentage, intensity variability and inverse difference moment) were left after redundancy reduction step. Cross-validation showed the accuracy of Logistic regression model was 80.0% (20/25), AUC was 0.790, sensitivity and specificity were 81.3% and 77.8% when cut-off was 0.45. Conclusion The radiomics model could provide important reference for differentiation between benign and malignant lesions in suspicious BI-RADS 4 findings. Key words: Breast neoplasms; Magnetic resonance imaging; Radiomics

Correlation between histogram analysis of dynamic contrast enhanced MRI and diffusion weighted imaging intravoxel incoherent motion quantitative parameters and Gleason score of prostate cancer

Objective To investigate the value and diagnostic efficiency of the quantitative dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) and intravoxel incoherent motion (IVIM) parameters using three dimention (3D)-histogram analysis for discriminating the Gleason score (GS) of prostate cancer. Methods A total of 53 patients pathologically confirmed as prostate cancer by systemic prostate biopsy who had routine, DCE and DWI-MRI scans were retrospectively analyzed. There were 15 cases for low-risk and 38 cases for intermediate/high-risk prostate cancer. The 3D ROI of all lesions based on T2WI was achieved by image registration to get the quantitative parameters of DCE-MRI and DWI-IVIM. The parameters of DCE-MRI contains: transfer constant (Ktrans), rate constant (Kep) and extracellular-extravascular volume fraction (Ve).The DWI-IVIM related quantitative parameters were ADC, diffusion coefficient (D), diffusion coefficient related to perfusion (D*) and perfusion fraction (f). Then the histogram analysis of these quantitative parameters was performed to get the mean, median, 25th percentile, 75th percentile, Skewness and Kurtosis. Using the Spearman rank correlation analysis to evaluate the correlation of these parameters and GS of prostate cancer. The diagnostic performance of these quantitative histogram parameters related to the GS in identifying low-risk and intermediate/high-risk of prostate cancer was carried by ROC. Results The Kep and Ktrans (mean, median, 25th, 75th) of DCE-MRI were positively correlated with GS (r value was 0.346 to 0.696, P<0.05). The ADC (mean, median, 25th, 75th), D (mean, median, 25th, 75th, Skewness, Kurtosis) and D*(25th) of DWI-IVIM were correlated with GS (r value was -0.544 to 0.428, P<0.05). The DCE-MRI quantitative parameters Kep (25th) had the highest area under curve (AUC, 0.961); The ADC (median) and D (25th) had higher AUC (0.832, 0.888) in the quantitative parameters of DWI-IVIM, the difference between Kep(25th) and ADC (median) was statistically significant (Z value was 2.212, P value was 0.027). The difference of AUC between Kep (25th) and D (25th), D (25th) and ADC (median) was not statistically significant (Z values were 1.027 and 1.398, P values were 0.162 and 0.304, respectively). Conclusion DCE and IVIM quantitative parameters (Kep, Ktrans, ADC, D) histogram analysis results are correlated with GS, and can be used for distinguishing low-risk from intermediate/high-risk prostate cancer. Key words: Prostate neoplasms; Magnetic resonance imaging; Comparative study

Correlation of quantitative parameters on dynamic contrast-enhanced MRI with prognostic factors of breast carcinoma

Objective To investigate the correlation between parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and prognostic factors (including enhanced morphology, tumor size, histological grade, nuclear grade) of breast carcinoma. Methods One hundred and thirteen breast cancer cases with 120 lesions confirmed histopathologically were retrospectively analyzed. All the patients underwent the DCE-MRI before the surgery, and the immunohistochemistry after the operation was performed to get the histological and nuclear grade. The volume transfer constant(Ktrans), rate constant (kep), and volume of extravascular extracellular space per unit volume of tissue(ve) were calculated through the DCE-MRI postprocessing. One hundred and three invasive ductal carcinomas were examined with the immunohistochemistry to get results of the histological and nuclear grade. Accordingly, the 103 lesions were divided in two subgroups: the tumors of histological grade Ⅰ, Ⅱ (low histological grade) and tumors of grade III (high histological grade); tumors of nuclear grade Ⅰ,Ⅱ (low nuclear grade) and tumors of grade Ⅲ (high nuclear grade). All the tumors were divided into mass-like type and non mass-like type according the enhanced morphology, as well as size ≤20 mm type and size >20 mm type respectively. Correlations between parameters and enhanced morphology, tumor size, histological grade, nuclear grade were analyzed through Mann-Whitney U test, the correlation between the tumor size and quantitative parameters was tested with Spearman correlation. Results Mean Ktrans was higher in tumors with mass-liketumors (n=92) than with non mass-like tumors(n=28), and the differences was statistically significant (P 0.05). There was no significant differences between tumor size≤20 mm(n=40) and size>20 mm (n=52) in mean Ktrans ,kep and ve respectively (P>0.05) .The mean maximal size of mass-like tumors was (2.38±0.95) cm, and there was no significant correlations between the tumors size and Ktrans (r=0.238, P=0.038), kep and ve (r values were 0.223 and 0.070, respectively, P values were 0.052 and 0.547 respectively) . Mean Ktrans, kep was higher in tumors with a high histological grade (n=22) than with a low histological grade(n=52), also was higher in tumors with a high nuclear grade(n=15) than with a low nuclear grade (n=56), with statistically significant differences (P 0.05). Conclusion There is correlation between parameters obtained from DCE-MRI and prognostic factors of breast cancers, with higher Ktrans and kep, or lower ve, indicating poor prognostic factors. Key words: Breast neoplasms; Magnetic resonance imaging; Prognostic factors

Correlation of quantitative perfusion parameters on dynamic contrast-enhanced MRI with prognostic factors and subtypes of breast carcinoma

Objective To investigate whether correlation exists between quantitative perfusion parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and different prognostic factors or immunohistochemical subtypes of breast cancers. Methods A retrospective analysis of DCE-MRI was performed in 87 breast cancer patients with 91 pathology confirmed breast lesions. All the patients underwent the immunohistochemistry after the operation, 80 breast cancer patients with 84 breast lesions were divided into different subtypes based on the immunohistochemical profiles. All the patients underwent plain MRI and DCE-MRI. The volume transfer constant (Ktrans), rate constant (kep) and volume of EES per unit volume of tissue (Ve) value were calculated. Results of the immunohistochemistry and observation results of the the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor- 2 (HER-2) were recorded. Subtypes were also categorized. The degree of the expression of Ki-67 was observed simultaneously. Among the 87 breast cancer patients (with 91 breast lesions), 68 were ER-positive,18 were ER-negative, 60 were PR-positive, 26 were PR-negative; 30 were HER-2 positive and 58 were HER- 2 negative. Eighty breast cancer patients (with 84 breast lesions) were divided into different subtypes:19 were Luminal A, 49 were Luminal B, 7 were HER-2 positive subtype and 9 were triple negative breast cancer (TNBC). The quantitative perfusion parameters with diffierent expression of the receptors were analyzed through Mann-Whitney U test, the correlation between the degree of the expression of Ki-67 and quantitative perfusion parameters was obtained with Spearman test. Furthermore, the distributions of the perfusion parameters between groups according to immunohistochemical subtype were compared using the Kruskal-Wallis test. Results Ktrans and kep value were higher in tumors with ER-negative and PR-negative than with ER-positive and PR-positive and difference was statistically different (P 0.05). The degree of the expression of Ki-67 was 5% to 90% the mean value was 33%, the median and interquartile range of Ktrans, kep and Ve value was 1.33/min (0.88/min), 2.63/min (2.34/min) and 0.51 (0.22) respectively. There was no significant correlations between the degree of the expression of Ki-67 and Ktrans and kep value (r value was 0.24 and 0.22 respectively, P value was 0.03 and 0.04 respectively), and the degree of the expression of Ki- 67 was not associated with Ve (r=0.00, P=0.97). Ktrans value was lower in Luminal A and Luminal B than that in HER-2 positive subtype and TNBC, kep value was lower in Luminal A and Luminal B than that in TNBC, and Ve value in Luminal A, Luminal B and HER-2 positive subtype were higher than that in TNBC, kep value was lower in Luminal B than that in HER-2 positive subtype, statistically significance was seen among them (P<0.05).Triple - negative breast cancer showed the highest kep value (3.99/min) and the lowest Ve value (0.41) than the other subtypes. Conclusion The different subtypes of breast cancer may be predicted to some extent with quantitative perfusion parameters, and there is no correlation between quantitative perfusion parameters and the prognostic factors. Key words: Breast neoplasms; Magnetic resonance imaging; Comparative study

Linear reference region model and Tofts model in dynamic contrast-enhanced MRI of discriminating benign and malignant breast lesions comparative study

Objective To investigate and compare the diagnostic values of linear reference region model (LRRM) and Extended Tofts model in quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) analysis of benign and malignant breast lesions under different temporal resolutions. Methods Eight five suspicious breast cancer women underwent bilateral DCE-MRI exam, 37 patients were benigns and 48 patients were malignants. Among those, 31 patients(15 malignant, 16 benign) were scanned with 18 s per phase, and 54 patients(33 malignant, 21 benign) were scanned with 7 s per phase, and they were assigned into breast cancer group, benign lesion group and healthy gland group proven by surgery or biopsies. For the same model, Ktrans values of the three groups under different time resolution were first analyzed using Kruskal-Wallis H rank sum test. Receiver operator curve (ROC) was used to analyse the diagnostic efficiency of Ktrans values. Results Under high and low temporal resolutions, Ktrans values of the healthy group were (0.048 ± 0.022) and (0.090 ± 0.040)/min for extended Tofts model,(0.301 ± 0.197) and (0.287±0.225)/min for LRRM model respectively.Ktrans values of the benign group were (0.289±0.163) and (0.211 ± 0.080)/min for extended Tofts,(0.624 ± 0.358) and (0.593 ± 0.165)/min for LRRM respectively.Ktrans values of the malignant group were (0.959±0.451) and (0.524±0.285)/min for extended Tofts,(1.576±0.935) and (0.956±0.180)/min for LRRM respectively.There were significant differences among the three different groups(P<0.05).Area under the ROC to differentiate benign and malignant breast lesions for Extended Tofts in high temporal, LRRM in high temporal, Tofts in low temporal and LRRM in low temporal were 0.941, 0.876, 0.850 and 0.933, with Ktrans cutoff values of 0.304, 0.917, 0.252 and 0.789/min,and sensitivity of 93.9%, 80.0%,80.0%, 80.0%;specificity of 85.7%, 90.5%, 81.2%, 87.5% respectively. Conclusion Under low temporal resolutions, Ktrans of LRRM model had better sensitivities and specificities in differentiation of benign and malignant breast lesions than Extended Tofts model, which was the opposite in high temporal resolutions. Key words: Breast neoplasms; Magnetic resonance imaging; Comparative study

Relationship between parameters of dynamic contrast-enhanced MRI and clinical stage of nasopharyngeal carcinoma

To evaluate the potential correlations between parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and clinical stages of nasopharyngeal carcinoma (NPC). Eighty-one newly diagnosed NPC patients received MRI examination. Clinical TNM stages and corresponding overall stages based on Chinese 2008 Staging System were determined. Pearson correlation coefficients were obtained to evaluate the potential correlations between DCE-MRI parameters of primary NPC lesions and clinical stages. Six cases were excluded from the study due to poor quality of images or too small tumor samples. The Ktrans,Kep, Ve, fPV, PeakT, Maxslop, CER, WoutSI, AUC90 and AUC180 values of 75 primary NPC tumors were (0.336 ± 0.133) min⁻¹, (1.419 ± 0.441) min⁻¹, 0.256 ± 0.100, 0.018 ± .010, (64.879 ± 15.975)s, (21.181 ± 5.507)s⁻¹, 1.348 ± 0.998, 0.515 ± 0.383, 16.177 ± 5.141 and 28.891 ± 9.511, respectively. Ktrans showed a positive correlation with overall stage (r=0.240, P=0.038), T stage (r=0.257, P=0.026) and M stage (r=0.438, P<0.001). A significant positive correlation was revealed of Ve with overall stage (r=0.418, P<0.001), T stage (r=0.466, P<0.001) and M stage (r=0.269, P=0.020). Negative correlation was found between Kep and T stage (r=-0.288, P=0.012). PeakT had positive correlation with overall stage (r=0.231, P=0.046) and T stage (r=0.318, P=0.005). AUC90 was revealed to have a positive correlation with overall stage (r=0.362, P=0.001), T stage (r=0.380, P=0.001) and M stage (r=0.446, P<0.001). AUC180 showed a positive correlation with overall stage (r=0.380, P=0.001), T stage (r=0.405, P<0.001) and M stage (r=0.423, P<0.001). No significant correlations for N stage with any DCE-MRI parameter were found. NPC in M1 stage had higher Ktrans, Ve, AUC90 and AUC180 values than NPC in M0 stage. There were significant (P<0.05) differences in Ktrans, Ve, PeakT, AUC90 and AUC180 values among different overall stages. Significant (P<0.01) differences in Ve, PeakT, AUC90 and AUC180 values were observed among different T stages. DCE-MRI parameters of primary NPC lesions have significant correlations with clinical stages. DCE-MRI parameters may act as imaging biomarkers for non-invasive assessment of the tumor microstructure, disease progression and aggressiveness of NPC.

Effects of dynamic transperineal ultrasound and dynamic magnetic resonance imaging defecography in the diagnosis of rectocele

Objective To evaluate the agreement between dynamic transperineal ultrasound (DTP-US)and dynamic magnetic resonance imaging defecography (DMRD) in the diagnosis of rectocele,and to compare the correlation and difference between the depth of rectocele measured by DTP-US and DMRD.Methods The clinical data of 18 female patients with rectocele who were admitted to the Third Affiliated Hospital of Nanjing University of Chinese Medicine from September 2011 to May 2012 were retrospectively analyzed.All patients received examination via DTP-US and DMRD,and the agreement of the 2 diagnosing methods was analysed.The accurate rates of the detection of other pelvic floor abnormalities by the 2 methods were calculated.The agreement of DTP-US and DMRD in diagnosing rectocele was analysed by Cohen's kappa test.The difference of the depth of rectocele measured by DTP-US and DMRD was compared by paired samplet test,and the correlation of the depth of rectocele measured by DTP-US and DMRD was analyzed by using the Pearson correlation coefficient.Results Of the 14 patients diagnosed by DTP-US,there were 7 patients with bladder prolapse,5 with unrelaxed pelvic floor,2 with uterine prolapse,2 with rectal internal mucous intussusception and 1 with enterocele; of the 18 patients diagnosed by DMRD,there were 12 patients with bladder prolapse,8 with unrelaxed pelvic floor,8 with uterine prolapse,6 with rectal internal mucous intussusception and 1 with enterocele.The agreement coefficient between DTP-US and DMRD in diagnosing rectocele was obvious (κ =0.737,P ＜ 0.05).The depth of the rectocele detected by DTP-US and DMRD were (15 ±6)mm (range,7-24 mm) and (27 ±7)mm (range,20-41 mm),with significant difference between the 2 groups (t =-16.124,P ＜0.05).There was a high coefficient between DTP-US and DMRD in detecting the depth of rectocele (| r | =0.874,P ＜ 0.05).The depth of rectocele detected by DMRD increased as the increase of depth of rectocele detected by DTP-US (| r | =1.000,P ＜ 0.05).Conclusions The agreement between DTP-US and DMRD in diagnosing rectocele is high.The depth of rectocele measured by the 2 methods not only has statistically significance,but also exists a high degree of correlation.While DTP-US is superior to DMRD in terms of quick diagnosis and better telerance of patients. Key words: Rectocele; Dynamic transperineal ultrasound; Dynamic magnetic resonance imaging defecography ; Constipation ; Outlet obstruction constipation

Role of magnetic resonance imaging for response evaluation and predictive value of tumor biomarkers in the neoadjuvant chemotherapy for breast cancer:a multi-center prospective study

To explore the value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in monitoring therapy responses and analyze the predictive value of tumor biomarkers in neoadjuvant chemotherapy for breast cancer. From August 2010 to August 2013, the patients diagnosed as primary invasive breast cancer were admitted into this multi-center study. All of them received 6 cycles of neoadjuvant chemotherapy and DCE-MRI during the procedure and underwent surgery. The associations between clinical therapy response and pathologic response as well as predictive factors were analyzed. As for evaluating neoadjuvant treatment response, DCE-MRI had statistically significant correlations with histopathology. PR negativity, HER-2 over-expression and high Ki-67 index were statistically correlated with pathologic complete response (pCR) (P < 0.05). DCE-MRI is a reliable method of assessing the response of neoadjuvant therapy for breast cancer. And the immunohistochemistry status of PR, HER-2 and Ki-67 were related with pCR.

To compare the role of Gd-EOB-DTPA dynamic contrast-enhanced MRI with multi-detector row computed tomography (MDCT) in patients with focal liver lesions

Objective To compare the role of Gd-EOB-DTPA dynamic contrast-enhanced mag- netic resonance imaging （DCE-MRI） with multi- detector row computed tomography （MDCT）, and to determine the sensitivity, specificity and accuracy in foca! hepatic lesions. Methods A retrospective a- nalysis was conducted on 32 patients with focal hepatic lesions who had undergone MRI and MDCT examinations. These patients were divided into two groups： the CT group and the MRI group. The results were analysed using receiver operating characteristic （ROC） curves. Result There were 185 focal hepatic lesions. The sensitivity, specificity and the area under the ROC curve （AUC） were 86.5%, 90.9%, 0. 855, respectively for the MRI group and they were significantly higher than the CT group （63.6%, 54.5%, 0. 532）. For detection of lesions 〈1 cm, the sensitivity, specificity and the area under the ROC curve （AUC） for the MRI group were 90%, 86.6%, 0. 886, respectively, which were also significantly higher than the CT group （50.5%, 45.5%, 0. 500）. When combined with pathological findings and follow-up, the diagnostic accuracy was 40.6% using Gd-EOB-DTPA DCE- MRI. Conclusion Gd-EOB-DTPA DCE-MRI has a higher detection rate, better accuracy and diagnostic value for focal liver lesions （〈1 cm） than MDCT. Key words: Gd-EOB-DTPA; Dynamic contrast-enhanced magnetic resonance imaging; Focal hepatic lesions