Diffusion-weighted Imaging Apparent Diffusion Coefficient Values Research Articles

Spin-echo and diffusion-weighted MRI in differentiation between progressive massive fibrosis and lung cancer.

We aimed to investigate the value of magnetic resonance imaging (MRI)-based parameters in differentiating between progressive massive fibrosis (PMF) and lung cancer. This retrospective study included 60 male patients (mean age, 67.0±9.0 years) with a history of more than 10 years working in underground coal mines who underwent 1.5 T MRI of thorax due to a lung nodule/mass suspicious for lung cancer on computed tomography. Thirty patients had PMF, and the remaining ones had lung cancer diagnosed histopathologically. The sequences were as follows: coronal single-shot turbo spin echo (SSH-TSE), axial T1- and T2-weighted spin-echo (SE), balanced turbo field echo, T1-weighted high-resolution isotropic volume excitation, free-breathing and respiratory triggered diffusion-weighted imaging (DWI). The patients' demographics, lesion sizes, and MRI-derived parameters were compared between the patients with PMF and lung cancer. Apparent diffusion coefficient (ADC) values of DWI and respiratory triggered DWI, signal intensities on T1-weighted SE, T2-weighted SE, and SSH-TSE imaging were found to be significantly different between the groups (p < 0.001, for all comparisons). Median ADC values of free-breathing DWI in patients with PMF and cancer were 1.25 (0.93-2.60) and 0.76 (0.53-1.00) (× 10-3 mm2/s), respectively. Most PMF lesions were predominantly iso- or hypointense on T1-weighted SE, T2-weighted SE, and SSH-TSE, while most malignant ones predominantly showed high signal intensity on these sequences. MRI study including SE imaging, specially T1-weighted SE imaging and ADC values of DWI can help to distinguish PMF from lung cancer.

Does the SUVmax of FDG-PET/CT Correlate with the ADC Values of DWI in Musculoskeletal Malignancies?

Purpose:To evaluate the correlation of maximum standardized uptake values (SUVmax) of 18F-Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) with the apparent diffusion coefficient (ADC) of diffusion weighted imaging (DWI) in musculoskeletal malignancies.Methods:Institutional ethics committee approved this retrospective study. Twenty-seven patients (mean age: 44.85 ± 24.07; 17 men and 10 women) with a total of 29 musculoskeletal tumors underwent both FDG-PET/CT and DWI between January 2017 and March 2020. Region-of-interest (ROI)-based maximal standardized uptake values (SUVmax) of the tumors were measured on FDG-PET/CT images. Two radiologists measured lesions’ mean and minimum apparent diffusion coefficient (ADCmean and ADCmin) using five distinct ROIs on DWI images. Pearson correlation analysis was used to assess the correlation between SUVmax and ADC values.Results:There were 18 soft tissue tumors (62.1%) and 11 bone tumors (37.9%) with a mean maximum diameter of 9.4 ± 6.2 cm. The mean SUVmax, ADCmean and ADCmin of the whole lesions were 12.93 ± 9.63, 0.85 ± 0.28 × 10–3mm2/s and 0.61 ± 0.27 × 10–3mm2/s, respectively. SUVmax had a weak correlation with tumor maximum diameter (r = 0.378, p = 0.043), whereas ADCmean and ADCmin had none. There was strong inverse correlation between SUVmax and both ADCmean (r = –0.616, p < 0.001) and ADCmin (r = –0.638, p < 0.001).Conclusion:In musculoskeletal tumors, quantitative markers of FDG uptake and diffusion restriction strongly correlate.

Performance of simultaneous multi-slice accelerated diffusion-weighted imaging for assessing focal renal lesions in pediatric patients with tuberous sclerosis complex.

Diffusion-weighted imaging (DWI) is a useful MRI technique to characterize abdominal lesions in children, but long acquisition times can lead to image degradation. Simultaneous multi-slice accelerated DWI is a promising technique to shorten DWI scan times. To test the feasibility of simultaneous multi-slice DWI of the kidneys in pediatric patients with tuberous sclerosis complex (TSC) and to evaluate the accelerated protocol regarding image quality and quantitative apparent diffusion coefficient (ADC) values compared to standard echoplanar DWI sequence. We included 33 children and adolescents (12 female, 21 male; mean age 10±5years) with TSC and renal cyst or angiomyolipoma on 3-tesla (T) MRI from 2017 to 2019. All studies included both free-breathing standard echoplanar DWI and simultaneous multi-slice DWI sequences. Subjective and quantitative image quality was evaluated using a predefined 5-point scale. ADC values were obtained for all renal cysts and angiomyolipomas ≥5mm. All statistical analysis was performed using Stata/SE v15.1. Simultaneous multi-slice DWI ADC values were slightly lower compared to standard echoplanar DWI for both renal cysts and angiomyolipomas (mean difference 0.05×10-3mm2/s, 95% confidence interval [CI] 0.40-0.50 and 0.024×10-3mm2/s, 95% CI 0.17-0.21, respectively, with P>0.1). Our results showed that renal lesions with ADC values >1.69×10-3mm2/s were all cysts, whereas lesions with values <1.16×10-3mm2/s were all angiomyolipomas. However, ADC values could not discriminate between lipid-rich and lipid-poor angiomyolipomas (P>0.1, for both sequences). A 55% reduction in scan time was achieved using simultaneous multi-slice DWI for abdominal imaging in children with TSC, with near identical image quality as standard DWI. These results suggest that multi-slice techniques should be considered more broadly as an MRI acceleration technique in children.

Association between liver diffusion-weighted imaging apparent diffusion coefficient values and other measures of liver disease in pediatric autoimmune liver disease patients

Multiple quantitative magnetic resonance imaging (MRI) methods have been described to noninvasively detect and characterize liver fibrosis, including diffusion-weighted imaging (DWI). To evaluate associations between liver MRI DWI apparent diffusion coefficient (ADC) values and clinical factors and other quantitative liver MRI metrics in pediatric patients with autoimmune liver disease (AILD). Fifty-seven research liver MRI examinations performed from January 2017 to August 2018 for pediatric AILD registry participants were evaluated. Liver DWI ADC values, liver and spleen stiffness (kPa), and iron-corrected T1 (cT1; Perspectum Diagnostics) were measured at four anatomic levels. Participant age, sex, and laboratory data (alanine aminotransferase [ALT], total bilirubin, alkaline phosphatase, gamma-glutamyl transferase [GGT]) were recorded. Spearman's rank-order correlation (rho) and multiple linear regression were used to evaluate the associations between liver ADC values and predictor variables. Mean (SD) participant age was 14.8 (4.0) years, 45.6% (26/57) were girls. Mean liver DWI ADC value was 1.34 (0.14 × 10-3) mm2/s. Liver ADC values showed weak to moderate correlations with liver stiffness (r = - 0.42, p = 0.001), spleen stiffness (r = - 0.34; p = 0.015), whole-liver mean cT1 (r = - 0.39; p = 0.007), ALT (r = - 0.50; p = 0.0001), and GGT (r = - 0.48; p = 0.0004). Multiple linear regression showed liver stiffness (p = 0.0009) and sex (p = 0.023) to be independent predictors of liver ADC values. Liver DWI ADC values are significantly associated with liver and spleen stiffnesses, liver cT1, ALT, GGT, and participant sex, with liver stiffness and sex remaining significant at multivariable regression. Liver ADC ultimately may play a role in multi-parametric prediction of chronic liver disease/fibrosis severity.

High-Spatial-Resolution Multishot Multiplexed Sensitivity-encoding Diffusion-weighted Imaging for Improved Quality of Breast Images and Differentiation of Breast Lesions: A Feasibility Study.

Multishot multiplexed sensitivity-encoding diffusion-weighted imaging is a feasible and easily implementable routine breast MRI protocol that yields high-quality diffusion-weighted breast images.Purpose: To compare multiplexed sensitivity-encoding (MUSE) diffusion-weighted imaging (DWI) and single-shot DWI for lesion visibility and differentiation of malignant and benign lesions within the breast.Materials and Methods: In this prospective institutional review board-approved study, both MUSE DWI and single-shot DWI sequences were first optimized in breast phantoms and then performed in a group of patients. Thirty women (mean age, 51.1 years ± 10.1 [standard deviation]; age range, 27-70 years) with 37 lesions were included in this study and underwent scanning using both techniques. Visual qualitative analysis of diffusion-weighted images was accomplished by two independent readers; images were assessed for lesion visibility, adequate fat suppression, and the presence of artifacts. Quantitative analysis was performed by calculating apparent diffusion coefficient (ADC) values and image quality parameters (signal-to-noise ratio [SNR] for lesions and fibroglandular tissue; contrast-to-noise ratio) by manually drawing regions of interest within the phantoms and breast tumor tissue. Interreader variability was determined using the Cohen κ coefficient, and quantitative differences between MUSE DWI and single-shot DWI were assessed using the Mann-Whitney U test; significance was defined at P < .05.Results: MUSE DWI yielded significantly improved image quality compared with single-shot DWI in phantoms (SNR, P = .001) and participants (lesion SNR, P = .009; fibroglandular tissue SNR, P = .05; contrast-to-noise ratio, P = .008). MUSE DWI ADC values showed a significant difference between malignant and benign lesions (P < .001). No significant differences were found between MUSE DWI and single-shot DWI in the mean, maximum, and minimum ADC values (P = .96, P = .28, and P = .49, respectively). Visual qualitative analysis resulted in better lesion visibility for MUSE DWI over single-shot DWI (κ = 0.70).Conclusion: MUSE DWI is a promising high-spatial-resolution technique that may enhance breast MRI protocols without the need for contrast material administration in breast screening.Keywords: Breast, MR-Diffusion Weighted Imaging, OncologySupplemental material is available for this article.© RSNA, 2020.

Correlation of Prognostic Factors of Invasive Lobular Carcinoma with ADC Value of DWI and SUVMax of FDG-PET.

Invasive lobular carcinoma (ILC) is the second most common kind of breast cancer. Diffusion weighted imaging (DWI) and positron emission tomography/computed tomography (PET/CT) are functional modalities for presenting the biological characteristics of breast cancer. The purpose of this article is to study the relationship between DWI or PET/CT and ILC's prognostic factors. The relationship between the apparent diffusion coefficient (ADC) values, standard uptake value (SUV)max and prognostic factors of ILC were statistically evaluated. The ADC values were lower in mass types of ILC. SUVmax was statistically higher in grade 3 and 4 background parenchymal enhancement and positive lymph node metastasis. ADC values of DWI and SUVmax of PET/CT can be helpful in the prediction of the prognosis of ILC.

MRI in the synchronic chemoradiotherapy of cervical squamous cell carcinoma.

This study aimed to explore the predictive value of the apparent diffusion coefficient (ADC) of diffusion weighted imaging (DWI) in evaluating the therapeutic effects of synchronic chemoradiotherapy of cervical squamous cell carcinoma by using the functional imaging of 1.5T MR. Fifty patients with cervical squamous cell carcinoma receiving synchronic chemoradiotherapy in the present hospital from October 2010 to February 2014 were enrolled in this study. MRI examination was performed on each patient before and after chemoradiotherapy. Eleven patients received an additional MRI examination when the in vitro cumulative radiation dose reached 36 Gy. The mean tumor ADC values of DWI sequence were measured before, under, and after chemoradiotherapy. At the end of the treatment, patients were divided into complete remission (CR) and partial remission (PR) groups on the basis of the residual tumors. Then the tumor ADC values and their changes before and after the treatment were analyzed using independent sample t-test. At the end of the treatment, 32 patients achieved CR and 18 patients achieved PR. The tumor ADC values increased gradually with the treatment, showing significant difference between before, under, and after the treatment (p < 0.01). The mean tumor ADC values were remarkably higher in CR group than in PR group (p < 0.001). The ADC values of MR functional imaging DWI can reflect the hydrone diffusion movement of tumor after the treatment, so that it is able to identify CR and PR in the patients, providing a new way and method for evaluating the therapeutic effects of cervical squamous cell carcinoma.

Apparent diffusion coefficient measurements with diffusion-weighted imaging for differential diagnosis of soft-tissue tumor.

To evaluate the diagnostic potential of apparent diffusion coefficient (ADC) values of diffusion-weighted imaging (DWI) in distinguishing malignant and benign soft-tissue tumors. Published studies were retrieved through comprehensive search in various computerized databases. High-quality studies relevant to ADC values of DWI in differential diagnosis of soft-tissue tumors were screened using our stringent inclusion and exclusion criteria for this meta-analysis. The standard mean difference with 95% confidence interval (95% CI) was estimated. Statistical analyses were performed using the STATA statistical software (Stata Co., College Station, TX, USA). Thirteen cohort studies were finally included, and these studies provided the required information on the diagnostic value of diffusion magnetic resonance imaging in soft-tissue tumors. The 13 studies contained a combined total of 344 malignant soft tumors and 315 benign soft tumors. The results of our meta-analysis revealed that mean ADC value in patients with malignant soft-tissue tumor decreased significantly in comparison with the ADC values obtained in patients with benign soft-tissue tumor (P < 0.001). Country-stratified analysis suggested that ADC value might play a predictive role in the differential diagnosis of soft-tissue tumors in China (P = 0.007), Egypt (P < 0.001), Germany (P = 0.001), Japan (P = 0.049), and The Netherlands (P < 0.001). Our results provide strong evidence that patients diagnosed with malignant soft-tissue tumors have low ADC values of DWI compared to those with benign soft-tissue tumors. Therefore, ADC measurements with DWI may be reliable in differential diagnosis of soft-tissue tumors.

The quantitative diagnostic capability of routine MR imaging and diffusion-weighted imaging in osteoporosis patients

ObjectivesTo determine the quantitative diagnostic capability of magnetic resonance imaging (MRI), compared to dual-energy X-ray absorptiometry (DEXA), for osteoporosis. Materials and MethodsEight male volunteers and eight patients underwent both DEXA and MRI. Results were obtained from each subject's L2 to L4, for a total of 48 lumbar vertebrae. Based on their bone mineral density (BMD) acquired from DEXA, the vertebrae were classified as follows: normal (n=28), osteopenic (n=0), and osteoporotic (n=20). All MR examinations were performed on a 1.5-T scanner to obtain T1-weighted imaging (T1WI), fat-suppression T2-weighted imaging (FS-T2WI), and diffusion-weighted imaging (DWI). These quantitative MR parameters were determined: T1WI and FS-T2WI signal-to-noise ratios and DWI apparent diffusion coefficient values. To determine the diagnostic capability of MRI as an osteoporosis indicator, MR parameters were assessed statistically. ResultsAll MR parameters significantly correlated with BMD (T1WI: r=−0.64, FS-T2WI: r=−0.36, DWI: r=−0.29), with significant differences among normal and osteoporotic vertebrae (P<.05). By receiver operating characteristic analysis, the area under the curve of T1WI was significantly higher than others (P<.05). When adapted as feasible threshold values, sensitivity, specificity, and accuracy of T1WI were 95.0% (19/20), 92.9% (26/28), and 93.8% (45/48), respectively. ConclusionRoutine MRI, in particular T1WI, had a potential for the assessment of osteoporosis.